Allow style for <stop> elements in the whitelist.  Allow gradients to refer to each other in the whitelist.  Update removeUnusedGrads() to account for this.
Allow style for <stop> elements in the whitelist.  Allow gradients to refer to each other in the whitelist.  Update removeUnusedGrads() to account for this.

git-svn-id: e52e7dec99011c9686d89c3d3c01e7ff0d333eee@1282 eee81c28-f429-11dd-99c0-75d572ba1ddd

BakerSky/svgedit,laddhoffman/svgedit,SVG-Edit/svgedit,centaurustech/svgedit,mynext/svgedit,SVG-Edit/svgedit,mynext/svgedit,bartuspan/svgedit,uche40/svgedit,beavis28/svgedit,laddhoffman/svgedit,ubbn/svgedit,bartuspan/svgedit,tremez/svgedit,BakerSky/svgedit,laddhoffman/svgedit,SVG-Edit/svgedit,thewenneur/svgedit,centaurustech/svgedit,progers/svgedit,BakerSky/svgedit,beavis28/svgedit,progers/svgedit,centaurustech/svgedit,uche40/svgedit,bartuspan/svgedit,tremez/svgedit,bartuspan/svgedit,BakerSky/svgedit,progers/svgedit,progers/svgedit,uche40/svgedit,tremez/svgedit,beavis28/svgedit,thewenneur/svgedit,beavis28/svgedit,thewenneur/svgedit,ubbn/svgedit,thewenneur/svgedit,laddhoffman/svgedit,tremez/svgedit,mynext/svgedit,mynext/svgedit,centaurustech/svgedit,ubbn/svgedit,ubbn/svgedit,uche40/svgedit