band grouping for spot4 take5 and tests

Added band grouping for spot4 take5 reader and created some tests
routines
Merge remote-tracking branch 'origin/spot5' into spot5

Conflicts:

	s2tbx-spot-reader/src/main/java/org/esa/beam/dataio/spot/dimap/SpotConstants.java
Merge remote-tracking branch 'origin/spot5' into spot5

Conflicts:
	s2tbx-spot-reader/src/main/java/org/esa/beam/dataio/spot/dimap/SpotConstants.java