treewide: Change URLs to HTTPS

Lots of URLs were HTTP redirect to HTTPS. Changed those and checked them
if there's actual content. Inspired by
https://github.com/NixOS/nixpkgs/issues/60004

pkgs/development/libraries/libgeotiff/default.nix

@@ -19,7 +19,7 @@ stdenv.mkDerivation rec {
 
   meta = {
     description = "Library implementing attempt to create a tiff based interchange format for georeferenced raster imagery";
-    homepage = https://www.remotesensing.org/geotiff/geotiff.html;
+    homepage = https://github.com/OSGeo/libgeotiff;
     license = stdenv.lib.licenses.mit;
     maintainers = [stdenv.lib.maintainers.marcweber];
     platforms = with stdenv.lib.platforms; linux ++ darwin;