Merge branch 'stable-1.2'

* stable-1.2:
  Add API checking using clirr
  Fix MergeCommandTest to pass if File.executable is not supported
  Fix ResolveMerger not to add paths with FileMode 0

Change-Id: I86e7194a40acd6dfa3d433f1d17c01bdf5bb0d9c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>