Moved IdentityStrategy to it's own class.
Renamed the StrategyWrapped prefix to just Strategy.

For example StrategyWrappedGraph is now just StrategyGraph.
Remove hiddens GraphStrategy methods. #403
Remove more references to hidden in docs/comments.
Remove reference to hidden in comments.
Changed reference from DefaultGraphStrategy to IdentityGraphStrategy.
Merge branch 'master' into check-docs