Merge branch 'feature/fix-implicit-buildmode-doc' into 'master'

Fix implicit buildmode documentation and adjust test accordingly

This basically turns the issue #21 into a feature by correctly describing the constraints of the implicit build mode and the meaning of its parameters. This invalidates the test against the old interface description which is hence dropped by this MR. As a consequence the bcrsimplicitbuild-test passes again.

See merge request !63