Surveys through redcap

[squirrelo]

This takes care of the actual survey logging and back and forth between redcap and AG. Needs some way of testing this communication, however.

Requires #579 Merged

[coveralls]

Coverage decreased (-2.9%) to 58.54% when pulling e2abeeb on squirrelo:surveys-through-redcap into 84d2c61 on biocore:redcap-integration.

[coveralls]

Changes Unknown when pulling 0286541 on squirrelo:surveys-through-redcap into * on biocore:redcap-integration*.

[squirrelo]

@EmbrietteH this is ready for review.

[EmbrietteH]

ping @wasade

[wasade]

Did a static analysis and looks with except missing tests for create_record and as_transaction. I'm particularly concerned about positive/negative tests for as_transaction in the context of a tornado handler, and whether failure conditions muck with tornado. Would it be possible to add a test or two?