Fix non-externalized string warnings in IndexDiff

Change-Id: Ia803182114f0e8b418428e03601f9afc6542ed28
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Do not swallow exception if IndexDiff hits invalid ignore param

Change-Id: I8a595e1f01a0731118d3c537be420222f7fec744
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>