Removed NilType equality.
Experimental leaf example runner
Added endWith(), beginWith(), contain() matchers
Added async support. Backfilled tests.
Renamed messagePostfix to postfix to be shorter.
Re-enabled matcher tests. Renamed equalTo -> equal
Updated readme.
Added support for contain, beginWith and endWith for some objective-c objects.

Postfixed Matcher to matcher classes.
Renaming.