BACKOUT #16890 : keep half pixel shift for default origin in OTB, but implies fixing SensorModelAdapter

Windows build are failing due to last two commit related to
Wunsed-parameter but I had added a fix which follows itk code
to make it portable across compiler(s) mainly Microsoft VC
Warning fix updated in Testing/Code/
BasicFilters, Common, IO, FeatureExtraction,
Learning, DisparityMap, Mutliscale
New fix added in - SpatialReasoning, Projections

ENH: Adding a helper class to hold duplicated code computing p/xs offset for Pleiades sensor bundles

BUG: #942 There is no reason why the origin coordinates should be (0.5,0.5) when there is no geotransform. This induces an error when calling sensor models (which assume origin is (0,0)

BUG: Multiple errors in Pleiades sensor model (invalid cast to Int32 and inconsistency with OSSIM sensor model convention, which is that the coordinate of the UL pixel center is (0,0)

ENH: remove warning when phr mode is activated by the application and extend long description to describe app modes