Resolve WB-421 Removed Files Remain Persistant in Manage Loaded Files Dialog:...

Resolve WB-421 Removed Files Remain Persistant in Manage Loaded Files Dialog: The problem was caused by having multiple files of the same type with the same name.  This could occur using the File Menu->Open Data File Dialog.  Now, when a file of a particular data type is loaded, Workbench will check to see if a file with the same data type and name is currently loaded.  If so, Workbench will alter the name of the file being loaded so that it is different than the name of any other files of the same type.  The name of the file is altered by inserting an underscore followed by a number immediately before the file extension's dot.  For example if the file melodic_IC.dscalar.nii is loaded and the user opens the same file with the File Open Dialog, the second instance of this file in memory will be renamed to melodic_IC_1.dscalar.nii.  By altering the filenames of duplicate files, it should also make it easier for the user to distinguish the duplicate flies in the user-interface such as the overlay selection.