Lookup and AbaLookup modules (API, database, et al.)

Unfortunately this is a rather large PR (which will only grow with time).

###### What's in this thing?

- DB access paradigm
- Models/entities
- A-whole-lot-cleaner `AbaLookup` and `Lookup` modules

###### What's remaining (that should be in this):

Hopefully just:

- [ ] Matching API
- [ ] Profile and schedule updating
- [ ] Validation/sanitization of data