Add support for tagged scenarios

Handle steps with tags

This is preformed by adding the methods:

    `(id)handleBeginScenarioWithHash:(NSDictionary *)hash`
    `(id)handleEndScenarioWithHash:(NSDictionary *)hash`

The tags are passed in a hash, and the above method names are generated
and invoked. The hash is not actually used in the methods.

v0.8

Updated to Xcode v5.x