ENH: working on adding multi-page component dialogs
BROKEN: various dialogs not working while I fix multi-page dialogs
BROKEN: nearly working again though!
DOCS: updated docs for visual stims with summary links for attribs

Also added doc on rendering info (OpenGL, shaders etc)
ENH: many improvements to layout of Component/Loop dialogs

nameLabel not working properly in loop dlg though
Merge branch 'feature-multiPageComponents'