Tidy up tests

[Arcath]

Although Adauth has tests for all its code they aren't laid out very well and a lot of advanced functionality is tested in the same file as making sure we can fetch a user.

Before 2.1.0 I would like to move them all around and seperate them out into meaningfully named files and folders

[jzohrab]

@Arcath - is this still an issue? Things look ok on first glance. If I can help here let me know, thanks.