Display matching invocations alongside their respective expectations in error message

[floehopper]

See #167. Display all the actual invocations recorded against both unsatisfied & satisfied expectations, including the parameter values passed into the method and the return value generated by the expectation. I'm thinking along the following lines:

foo = mock('foo')
foo.expects(:bar).with(1).returns('a')
foo.stubs(:bar).with(2).returns('b').then.returns('c').then.raises(StandardError)

3.times { foo.bar(2) }
foo.bar(3)

unexpected invocation: #<Mock:foo>.bar(3)
unsatisfied expectations:
- expected exactly once, not yet invoked: #<Mock:foo>.bar(1)
satisfied expectations:
- allowed any number of times, invoked 3 times: #<Mock:foo>.bar(2)
  - #<Mock:foo>.bar(2) # => 'b'
  - #<Mock:foo>.bar(2) # => 'c'
  - #<Mock:foo>.bar(2) # => raised StandardError

It would also be nice to record any yields that occur.

We might only want to enable this using a verbose configuration option.

[floehopper]

Implemented in #394 & #410.