implement Directory Reference

Directories
directory	Display
directory	DisplayCanvas
directory	DisplayDatas
directory	DisplayEvents
directory	DisplayShapes
directory	ds9
directory	QtAutoGui
directory	QtPlotter
directory	QtViewer
directory	region
directory	RegionShapes
directory	Utilities
Files
file	Display.h [code]
file	DisplayDatas.h [code]
file	DisplayErrors.h [code]
file	DisplayEvents.h [code]
file	DisplayShapes.h [code]