Fix a few links in readme

Author: ronja-koistinen

readme.md

@@ -129,9 +129,9 @@ As defined by Wikipedia a shim is a small library that transparently intercepts
 - [IIIF Curation Viewer](http://codh.rois.ac.jp/software/iiif-curation-viewer/) - A general IIIF viewer with added focus on curation and ordering of cropped IIIF images. [Demo](http://codh.rois.ac.jp/software/iiif-curation-viewer/demo/?curation=https://gist.githubusercontent.com/2SC1815J/18e1228c52a6650c64902142ed7496f8/raw/7a247b64b6e22357e83f573b7283e31f3111af68/curation_kibutsu.json&pos=4)
 - [Internet Archive BookReader](https://github.com/internetarchive/bookreader) - A viewer developed by the Internet Archive, specially suited for viewing books.
 - [Micrio](https://micr.io/iiif) - High-performance client with WebAssembly/WebGL engine and additional storytelling elements. Also offering full server IIIF support.
-- [Mirador](projectmirador.org/) - Multi-up workspace. See also [Awesome Mirador list](https://github.com/ProjectMirador/mirador-awesome).
+- [Mirador](https://projectmirador.org/) - Multi-up workspace. See also [Awesome Mirador list](https://github.com/ProjectMirador/mirador-awesome).
 - [Tify](https://github.com/subugoe/tify) - Slim and fast IIIF document viewer built with Vue.js.
-- [Universal Viewer](universalviewer.io/) - Rich embeddable interface.
+- [Universal Viewer](https://universalviewer.io/) - Rich embeddable interface.
 
 ### Image viewers (Image API only)