Fix: #209

Also, while we're here... dodge making modular pull requests so that we can get the thing running again before merging.

• Convert travis-based tests to github actions so they actually run
• Don't raise NotImplementedError in datajoint module on import - what the hell was i thinking lmao
• don't access deprecated alias np.float, just use float
• fix a bunch of docs stuff to make it build
• update dep versions and remove some upper bounds