add operators to PropertyValue
make Application::addLogging default to an empty logname ("-d")
fix missing _internal:: before some NDimensional
Merge branch 'api_change' into ch_propvalue
allow direct "="-operations only on "real" Value objects / not XXXXBase
Merge branch 'ch_value' into ch_propvalue

Conflicts:
	lib/Core/CoreUtils/propmap.hpp
add ValueBase::apply to a apply a basic value to a Value without knowing its type
Merge branch 'ch_value' into ch_propvalue
cleanup and add some tests
adapt nifti_sa