Translator/Loader refactor

[parkan]

Oook this ended up getting kind of out of scope, plz take a look (needs some style cleanup and a slight rejigger with how self-types are [not] used)

[parkan]

Ok, this should be good to merge now (once tests pass)

[parkan]

Ok and good to merge git-wise now too. Feel free to comment, I think I addressed most concerns though

[parkan]

Ok upon self-review things that are missing are:

• did not actually move out JsonFactory construction out of everywhere
• parser still has a few places where it can throw and nothing catches
• TateIngestionSpec is still commented out though maybe we don't actually need to integration test that part

Anything else?

[parkan]

@bigs: if you want to take some of this off my plate, I would suggest doing a throw safety pass through the parser. Specifically, calls to nextToken like here can throw on malformed json and should be wrapped like so

The other related things are:

• Catching the original parser throwing, which requires using my wrapped createParser, there's a few spots where that should happen
• Possibly pulling the nextToken calls that consume nulls into the above call (I don't like remembering to call this manually)