Refactored tests a bit

Split message receiving tests into two types: Events firing and actual
message parsing tests. Even though message parsing will always result in
events firing, I want the delineation to be clear, especially because
there will definitely be multiple parsing tests for some object types.
If the event stops firing for whatever reason, I want to see that the
event firing test fails along with any tests dependent on that
functionality. Without the split, I'd just see a bunch of parsing tests
fail, even though the issue isn't with parsing.