mmstudio: Expanded available ImageJ repated ImageUtils a bit

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14640 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
MultiChannelShading: Renamed menu entry to Flat-Field Correction.  Plugin now works for all byte and short images.  Appropriately transforms background and flatfield images when images were acuqired with different binning and/or ROI setting.  Needs extensive testing in practice.

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14641 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd