Remove SquidUpdate::VarnishPurgeKey
Introduce ScribePurge class
Apply stylize.php on ScribePurge.class.php
Wiki.php: add RestInPeace hook
Send only unique URLs to the purger
Run stylize.php
PHPdoc updated
Merge pull request #2728 from Wikia/bac-1285-purge-unique-urls

BAC-1285: Send unique URLs to the purger queue