Refactored #check method unit tests

Removed useless messages (they where residual from the old QUnit version, and do nothing more than describe the comparison).
Resorted them as success, fail, type errors.
WIP: Naive unit tests added for #check with throws

They basically just check that #check throws an error when it fails if the throws flag is set to true.
They do not check that the content of the error is as expected. Will do that later.