Why:
* When `delegate_method` was modified a while back to add Doublespeak
and use MatcherContext, Shoulda::Matchers::Independent became unable
to be required independently.
To satisfy the above:
* Require Doublespeak and MatcherContext within
`delegate_method_matcher.rb`.
* Add an acceptance test to ensure that Independent stays independent.
Secondary-Author: jc00ke <jesse@jc00ke.com>