app: remove old TODO

This test is kind of a end-to-end for app creation, and should not be
simpler or smaller.
app: import  testBadHandler from api package

Slight different, but still the same.
app: import gandalf related tests from api package

Let's kill createAppHelper.
app: introduce the "teams" parameter to CreateApp

This parameter defines which teams should have access to the app.
app: moving errors
app: add test for custom error types
app: validating the presence of teams when creating a new app

One step closer to killing createAppHelper.
api: drop createAppHelper function

hallelujah :-)
api, cmd/crane, cmd/tsuru/developer: stop using "package documentation"

godoc is dropping it.
check-fmt: disable go vet temporarily

It's broken at tip, again :-(

See http://golang.org/issue/4906.
travis: remove trailing popd

They don't matter.