Update and Add Group rotation feature to SCDCalibratePanels

[mantid-builder]

Original Reporter: @RuthFromDuluth

Original Owner: @RuthFromDuluth

-The SaveDetCal now saves ALL the panels, not just the ones used.
-When algorithm is rerun, there is now a lot of error messages because the old output is not removed.
-Default option for no preprocessing
-Check grouping option. A bad lexical cast occured

NEW
-When panels are grouped, rotate every member of the group about the center of the instrument
-Incorporate sample offsets to get better results.

[mantid-builder]

This issue was originally trac ticket 6339