Testconfig: Adding nightly build jobs to CI to test Qt5

These jobs are triggered by run and each one executes same stages
as Qt5_<branch>_Integration does with same options.

Change-Id: I5a53978514b2549274c797215fec824742fa2b24
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>