[466552] Increase priorities of conflict mergers

Increases the priority of the PseudoConflictMerger to 75 and
the priority of the ConflictMerger to 100. This fixes merging issues
originating from a too small PseudoConflictMerger priority value. Also
offers a lot more possibilities for merger prioritizations by clients.

Includes a testcase for UML models.

Bug: 466552
Signed-off-by: Stefan Dirix <sdirix@eclipsesource.com>
Change-Id: I29f964a47fb80d34cc6546afadab52d45204c12d
9 files changed