Merge alt_api_controller into alpha.

Herculean refactors and controversial decisions made unilaterally... all for great good.

* Almost all changes stayed isolated to the api_controller but big decisions were made there, namely using closures to reduce code duplication.
* While changes did not propagate on their own, I also modified some connections between modules that didn't feel great.
* This also left automated unit tests for the front-end handlers behind. I want to bring those back ASAP but the README says 80% code coverage and not 100% code coverage for a reason. I think we spend our 20% now.