enhance test to fix Coverity issue CID 60867 : EC: Comparing incompatible types for equality
refactor code to fix CID 60865 : dereference null return value
add test applying 180° step, issue #147
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Merge remote-tracking branch 'origin/master'
use circular average to make sensororientation less jumpy, issue #147
remove whitespace
wrap long line
CID 60866, 60868 : fix Coverity issue : Casting from integer values
introduce CircularAverage class to make sensor based orientation value less jumpy, close #147
Merge branch 'master' into coverity_scan

Conflicts:
	ChangeLog