Replace fakestudies and fakefiles with a fakeorgs command

[dankolbman]

In order to bootstrap mock data, we currently run fakestudies followed by fakefiles. This creates a handful of fake studies and then will add a bunch of fake files to those studies.
This is a little non-sensible because the study factory should call on the file factory to create studies whenever a fake study is created. Furthermore, now with the idea of organizations, the organization factory should create studies which will create files. If these factories are setup correctly, we should be able to create a simple fakeorgs command which will call OrganizationFactory.create_batch(n) which will take care of all the mock data setup.

[gsantia]

The way it's setup now you can decide how many studies/files you want created, but I assume this won't be the case for a single fakeorgs command. Should we just use the default values for both of these then?

[dankolbman]

We could use the current defaults but perhaps we could still retain the flags.
User's could do something like: python manage.py fakeorgs --orgs 2 --studies 5 --files 3 and it would give 2 orgs each with 5 studies that contain 3 files.
I'm not sure those would be that useful, however, so maybe just let the subfactories decide how to do it. We can still keep the fakestudies and fakeorgs commands in case we need a specific number of studies/files.