ManualStretchType.h: 2011-11-04 Steven Lambright - This should be much, much...

ManualStretchType.h: 2011-11-04 Steven Lambright - This should be much, much easier to use now. Fixes #567. 
StretchType.h: 2011-11-04 Steven Lambright - Split up updateGraph and updateTable and moved them to protected. The manual stretch type needs to choose explicitly when to update the table, but always wants to update the graph. 

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@3678 41f8697f-d340-4b68-9986-7bafba869bb8