Rework threshold maps test to allow for using any DAC. This also exposes
the new API functionailty of adjusting the threshold level (default is
still 50% level as it was before)
Merge branch 'master' into threshmaps
Merge branch 'master' into threshmaps

Conflicts:
	tests/PixTestThreshMap.cc
	tests/PixTestThreshMap.hh
Re-introduce ThreshMaps, used by CERN people.
Merge branch 'master' into threshmaps
Move ThresMaps test to user space (usertests directory). It provides a
full-featured access to the Threshold Map functionality offered by pxarCore.
This includes the possibility to set the desired threshold.
Usertests: PixTestThresMap: also allow definition of the scanning step size.
Merge pull request #205 from simonspa/threshmaps

New User Test: "PixTestThreshMap"