This change adds a missing HttpResponse return to the TravisCI

webhook. We didn't notice this before because by the time the error

gets triggered, everything has already been processed and updated, so

it's just something that triggers an error email to the server admins.
While I was doing this I found there were a handful of test failures.

Some args-vs-kwargs problems were causing a few tests to error out,

either with a duplicate kwarg error or a type error; these were easily

fixed by specifying kwarg names for all IntegrationForm

instantiations. There were also some warnings coming from kgb about

missing owner= parameters.

Ran unit tests.