Enhancements to the Ginga FITS toolkit

	modified:   ginga/Control.py
	modified:   ginga/FitsImage.py
	modified:   ginga/PythonImage.py
	modified:   ginga/RGBMap.py
	modified:   ginga/cairow/FitsImageCairo.py
	modified:   ginga/gtkw/FitsImageGtk.py
	new file:   ginga/misc/plugins/SAMP.py
	modified:   ginga/qtw/FitsImageQt.py
	modified:   ginga/qtw/QtHelp.py
	modified:   scripts/ginga
	renamed:    ginga/util/grc.py -> scripts/grc.py

- refactored support for saving images as 3-color RGB files
  - allows easy creation of "screen grabs"
- moved ginga remote control program to scripts directory
- added an initial cut at a SAMP plugin
  - to run, start ginga with the --modules=SAMP option
- fixed a possible bug with the importing of PIL in PythonImage.py