MWEB-1066: fixed PHP fatal error by using instance of WikiPage instead of Article instance
corrected PHPDocs and used WikiPage instances instead of Article
CR changes: removed &, used short array notation
CR changes: cleanup in vars names
brought back ampersants since it will not work unless we change it everywhere
Merge pull request #5147 from Wikia/MWEB-1066

MWEB-1066 P2 fix: PHP fatal error on production