i18n - special page and namespace aliases - bugid 68841

A number of special page and namespace aliases have been added for some extensions as requested in https://wikia.fogbugz.com/default.asp?68841 . All of the aliases tagged 'important' and some of the 'less urgent' ones have been added.

As I'm fairly new to Github, I'd appreciate a review of the commits. If everything is fine and the commits get merged, I'd be happy to add the rest of the aliases listed in that ticket (if I can find where they live ;))