[2.0] Refactor Injection models into different types

[dbirman]

Is your feature request related to a problem? Please describe.
@saskiad Please expand on goals

Describe the solution you'd like

• TBD
• Upgrader from v1.x to 2.0

[saskiad]

I think this is something @dyf wanted. Is the idea to not have the Injection and BrainInjection classes that get inherited by NanojectInjection and Iontophoresis and just repeat all those fields?

I do think we can consider removing:

• recovery time
• instrument_id
• duration
• bregma_to_lambda_distance (though this might be good)

These are things NSB tracks but could be in a AIND extension if we really want to keep them