Move info about PEP 503 to the top

Author: insolor

README.md

@@ -1,6 +1,6 @@
 # Dwarf Fortress localization project Python package index
 
-The index is build from the [index.yml](index.yml) file.
+The index is build from the [index.yml](index.yml) file (reference: [PEP 503](https://peps.python.org/pep-0503/)).
 
 View the index: <https://dfint.github.io/pypi-index/>
 
@@ -16,5 +16,3 @@ Using poetry:
 poetry source add --priority=explicit dfint https://dfint.github.io/pypi-index/
 poetry add --source=dfint df-translation-toolkit
 ```
-
-Reference: [PEP 503](https://peps.python.org/pep-0503/)