Intrepid2: refactor branch documentation

Created by: rppawlo

In the intrepid2 refactor branch, some functions were modified to require scratch space. However the doxygen documentation was not modified to describe the scratch space requirements. Without diving into the implementation I don't know what the rank or size of the DynRankView scratch space should be prior to calling the function.

An example of this is in the Intrepid2_FcuntionSpaceTools.hpp in the computeFaceMeasure() function.

This ticket is to request documentation be updated. Mention rank and size requirements for scratch space.