Support for FlaggedRevs patrolling

Replaces basic built-in MediaWiki patrolling. Will always only review
at the most basic "accuracy level", which is what every Wikimedia wiki
uses.

Added 'ActionReview' to 'enum Action' to support FlaggedRevs API
queries.

Added config option 'PatrollingFlaggedRevs' / 'patrolling-flaggedrevs'
to enable this feature, false by default.
s/char */const char */
Register PatrollingFlaggedRevs in configuration.hpp too
Merge pull request #71 from MatmaRex/flaggedrevs

Support for FlaggedRevs patrolling