i18n: consistency tweaks

* replace "article" by "page"
* add explicit GENDER support to "mobile-frontend-profile-usertalk"

Spotted by Siebrand
http://translatewiki.net/wiki/Thread:Support/About_MediaWiki:Mobile-frontend-mainpage-cta-button/en
http://translatewiki.net/wiki/Thread:Support/About_MediaWiki:Mobile-frontend-mainpage-cta-prompt/en
http://translatewiki.net/wiki/Thread:Support/About_MediaWiki:Mobile-frontend-profile-usertalk/en_%283%29

Change-Id: Ie4de56e931879e8230593ddb07287315dbdc9f90
Merge "i18n: consistency tweaks"