Adding monadic find: findMOf and ifindMOf

Added general shortcutting versions of these two functions to
Control.Lens.Fold
This is my first git push ever, so let me know if something is messed
up. I tried to match the style and conventions for findOf and ifindOf.

findMOf :: (Monad m, Iso s a)     -> (a -> m Bool) -> s -> m (Maybe a)
and
ifindMOf :: Monad m => IndexedLens i s a      -> (i -> a -> m Bool) -> s
-> m (Maybe a)
Need to add new functions to export list
Simplified condensing due to an API change in `split`.
Used equality witness to eliminate unsafeCoerce in tinplate.
Eliminated the rest of the unsafeCoerces in Data.Data.Lens.
INLINE Data.Data.Lens.mightBe.
Merge branch 'master' of github.com:ekmett/lens
Added Control.Lens.Cons examples.
INLINE
Added Control.Lens.Traversal.partsOf examples.
Alternative is good enough for failover.
Fix ifindOf docs typo.
Added Control.Lens.Traversal.singular examples.
the documentation for 'Iso' should use 'over' instead of 'set' .
Merge pull request #314 from nushio3/master

Fix documentation on Control.Lens.Iso
Added 'zlib' support

Since 'zlib' is in the platform, it seems only reasonable.
Merge pull request #317 from pthariensflame/topic/zlib-lens

Added `zlib` support
Merge pull request #300 from tomberek/master

findMOf and ifindMOf
Switch from MonadCatchIO-transformers to exceptions.
Eliminated SAFE ifdefs from Data.Data.Lens