Update extensions.tpl and migration list (#76)

* Update extensions.tpl

* Update migrate_from_classical.md

Author: fcollonval

extensions.tpl

@@ -26,7 +26,7 @@ This a list of nice JupyterLab extensions not part of ``jupyterlab-contrib`` org
 
 ### Editors
 
-- [Code Formatter](https://github.com/ryantam626/jupyterlab_code_formatter): Easily beautifies Python code inside JupyterLab using one of the formatters: Black/YAPF/AutoPEP8.
+- [Code Formatter](https://github.com/jupyterlab-contrib/jupyterlab_code_formatter): Easily beautifies Python code inside JupyterLab using one of the formatters: Black/YAPF/AutoPEP8.
 - [Collapsable Headings](https://github.com/aquirdTurtle/Collapsible_Headings): Allows to collapse an entire group of cells under the same header
 - [DrawIO](https://github.com/QuantStack/jupyterlab-drawio): An extension to draw diagrams in JupyterLab.
 - [Go to definition](https://github.com/krassowski/jupyterlab-go-to-definition): Allows you to <kbd>Alt</kbd> + <kbd>click</kbd> on a variable to jump to its definition.

migrate_from_classical.md

@@ -13,13 +13,13 @@ to [JupyterLab](https://jupyterlab.readthedocs.io/en/stable/) or
 | [(some) LaTeX environments for Jupyter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/latex_envs/README.html) |  |  |
 | [2to3 Converter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_2to3.html) |  |  |
 | [AddBefore](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/addbefore/readme.html) | Built-in feature (press <kbd>A</kbd> in command mode) | 1+ |
-| [Autopep8](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_autopep8.html) | [jupyterlab_code_formatter](https://ryantam626.github.io/jupyterlab_code_formatter/index.html) extension | 2, 3 |
+| [Autopep8](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_autopep8.html) | [jupyterlab_code_formatter](https://jupyterlab-code-formatter.readthedocs.io/) extension | 2, 3 |
 | [AutoSaveTime](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/autosavetime/README.html) | Built-in feature (Settings → Autosave Documents; Advanced Settings → Document Manager) | 1+ |
 | [Autoscroll](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/autoscroll/README.html) |  |  |
 | [Cell Filter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/cell_filter/README.html) | Built-in Table of Contents heading cells can be filtered by cell tags | 2.2+ |
 | [cite2c](https://github.com/takluyver/cite2c) | [jupyterlab-citation-manager](https://github.com/krassowski/jupyterlab-citation-manager) extension | 3+ |
 | [Code Font Size](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_font_size/README.html) | Built-in feature (View -> Presentation Mode or Settings -> JupyterLab Theme) | 1+ |
-| [Code prettify](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_code_prettify.html) | [jupyterlab_code_formatter](https://ryantam626.github.io/jupyterlab_code_formatter/index.html) extension | 1+ |
+| [Code prettify](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_code_prettify.html) | [jupyterlab_code_formatter](https://jupyterlab-code-formatter.readthedocs.io/) extension | 1+ |
 | [Codefolding](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/codefolding/readme.html) | Built-in feature (Advanced Settings -> Notebook -> codeCellConfig.codeFolding) | 1+ |
 | [Codefolding in Editor](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/codefolding/readme.html) | Built-in feature (Advanced Settings -> Text Editor -> editorConfig.codeFolding) | 1+ |
 | [Collapsible Headings](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/collapsible_headings/readme.html) | Built in feature since 3.1 ([PR](https://github.com/jupyterlab/jupyterlab/pull/10260)), for older versions use [aquirdturtle_collapsible_headings](https://github.com/aquirdTurtle/Collapsible_Headings) extension | 1+ |
@@ -40,9 +40,9 @@ to [JupyterLab](https://jupyterlab.readthedocs.io/en/stable/) or
 | [Hide input all](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/hide_input_all/readme.html) | Built-in feature (View -> Collapse All Code) | 1+ |
 | [Highlight selected word](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/highlight_selected_word/README.html) | Built-in feature (Edit -> Find...) | 2+ |
 | [highlighter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/highlighter/readme.html) |  |  |
-| [Hinterland](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/hinterland/README.html) | [jupyterlab-lsp](https://github.com/krassowski/jupyterlab-lsp) extension | 2+ |
+| [Hinterland](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/hinterland/README.html) | [jupyterlab-lsp](https://jupyterlab-lsp.readthedocs.io) extension | 2+ |
 | [Initialization cells](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/init_cell/README.html) | [jupyterlab-autorun-cells](https://pypi.org/project/jupyterlab-autorun-cells) extension | 2 |
-| [isort formatter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_isort.html) | [jupyterlab_code_formatter](https://ryantam626.github.io/jupyterlab_code_formatter/index.html) extension | 1+ |
+| [isort formatter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/code_prettify/README_isort.html) | [jupyterlab_code_formatter](https://jupyterlab-code-formatter.readthedocs.io/) extension | 1+ |
 | [Keyboard shortcut editor](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/keyboard_shortcut_editor/README.html) | Built-in feature (Advanced Settings -> Keyboard Shortcuts) | 1+ |
 |  | [jupyterlab-shortcutui](https://github.com/jupyterlab/jupyterlab-shortcutui) extension | 2+ |
 | [Launch QTConsole](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/qtconsole/README.html) |  |  |
@@ -73,7 +73,7 @@ to [JupyterLab](https://jupyterlab.readthedocs.io/en/stable/) or
 | [table_beautifier](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/table_beautifier/README.html) |  |  |
 | [Toggle all line numbers](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/toggle_all_line_numbers/readme.html) | Built-in feature (View -> Show Line Numbers) | 1+ |
 | [Tree Filter](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/tree-filter/readme.html) | Built-in feature | 3+ |
-| [Variable Inspector](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/varInspector/README.html) | [lckr-jupyterlab-variableinspector](https://github.com/lckr/jupyterlab-variableInspector) extension | 1+ |
+| [Variable Inspector](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/varInspector/README.html) | [lckr-jupyterlab-variableinspector](https://github.com/jupyterlab-contrib/jupyterlab-variableInspector) extension | 1+ |
 | [zenmode](https://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/zenmode/README.html) | Built-in feature | 1+ |
 
 If you don't find what you are looking here or in the web, you can always start coding a new extension; for