Avoid calling User::getSkin and remove pre-1.19 compat

Change-Id: I5ae20a833538a45de01fe3599eeb9c7b52ab17fe
Replace deprecated/removed $wgExtensionAliasesFiles

Change-Id: I24dfe50d4fb2e77724823e2ae88ff3620b468add
Extension has moved to GitHub. Make that clearer

Converted the remaining files to use Unix/LF line endings
instead of Windows/CRLF.

Bug: 63374
Change-Id: I7db4b4f8ce5ac71f90ee3d7554f829a9bc41cf97