raise your test coverage

this PR attempts to improve the test coverage. it does so by simply calling all urls and submitting all forms.

please do not merge yet, it's not done, i want to get feedback first.

the reason i put all the urls in one test is test run time. a test needs roughly half a second, so all 60 urls would need half a minute, which is quite a lot. now it needs about 4 or 5 seconds.

same with the failing forms, as they should not modify the database either.

@02strich, is there anything that is fundamentally wrong with theses tests? what would you do differently?
please add comments to make clear what the tests actually do. in the first case its a login key that does not exist, the second is valid and the third one expired.