* WikiPage::getParserOutput() requires a ParserOptions object (and optionally the revision ID) instead of an User object, removes an hidden dependency on $wgLang. For this reason, WikiPage::isParserCacheUsed() now also uses a ParserOptions object instead of an User object (doesn't change anything in the code except the variable name and it's not called in extensions)
* Moved PoolWorkArticleView to WikiPage.php and added an entry in the AutoLoader and moved output-related stuff directly in Article::view() so that in can be shared with WikiPage::getParserOutput() (removes code duplication, etc.)
* Added the revision ID to the PoolCounter key so that it knows which revision is being parsed and doesn't wait for another parse operation with same options but different revisions
* Removed Article::doViewParse(), Article::tryDirtyCache() and Article::getOutputFromWikitext() since they are now integrated in PoolWorkArticleView and Article::view() and there are no callers in extensions. This also fixes a bug since Article::doViewParse() will get another ParserOptions instance with special options set in Article::view() not be repercuted.
* Updated DifferenceEngine to use the new system
* Updated docs/memcached.txt to correct method names
use the same parsercache entry for articles without <math> tags.
The cache key format is kept as a fallback so the old cached entries can be reused.
Should boost parsercache hits, but it also makes easier to pollute the parsercache by tag hooks that behave
badly, directly using $wgUser or $wgLang.
Extensions hooking PageRenderingHash now see !edit=0 and the !printable=1 bits.
Fixes bug 24714 - Usage of {{#dateformat: }} in wikis without $wgUseDynamicDates can lead to unexpected results
Builds upon r70498, r70498, r70501, r70517, r70651, r70653, r70765, r70780.
