Fix removeBL for 3D movies

[ethanbb]

Description

This PR is mainly focused on making sure local_correlations_movie works for 3D movies, by adding an is3D flag for passing to caiman.load and also slightly modifying movie.removeBL. I also fixed other occurrences in local_correlations.py where caiman.load is used without an is3D flag; however, I have not tested whether all these functions actually work for 3D movies.

This fix is necessary to get mesmerize-core's motion correction routine to work for 3D data. But I'd understand if you want to make it a little more broad.

Type of change

Please delete options that are not relevant.

• [x] Bug fix (non-breaking change which fixes an issue)

Has your PR been tested?

caimanmanager test and caimanmanager demotest pass. I tested manually by running some of my data through local_correlations_movie (both from mesmerize-core and otherwise).