allow/non/lims/filepaths

[danielsf]

This PR makes it possible for users to specify filepaths that are not specific to the Allen Institute LIMS when instantiating a MovieJSONGenerator. This will be useful for outside users, and Allen Institute users, since the naming convention for our motion corrected movies may change.

I would also like to talk about that massive try/except block in MovieJSONGenerator.__data_generation__ My experience has been that it has obscured failures that I actually want to fix in my configuration files. Is there a reason we don't want to alert users when their input data is ill-formed?