Updated plasma themes

[Jamboarder]

I went ahead and updated Elegance and Silicon to essentially match the most recently published versions.  The updates the theme authors made look *much* better than the terribly out-of-date and partially broken versions in trunk.  I have a message out to the author of Heron since the package available on kde-look seems corrupted somehow (many of the bugs with the svn version are said to have been fixed - just need the updated package).

So please go ahead and use these updated themes for testing (kdeartwork/desktopthemes) so we can identify any visual bugs in support of the artwork freeze.  Slim Glow and Aya are up-to-date as well.  I'll keep and eye out for any additional updates from these theme authors and try to make sure the versions in trunk are up-to-date when 4.2 final is tagged.

Hope this helps,
Andrew (Jamboarder) Lake

P.S. Notice a couple minor theme-change regressions that popped up in the last day: systray expander doesn't update, the icon in the extender dragger gets HUGE for some theme changes, and the task group expander (the little triangle) is sometimes stretched out or missing.  If prompted, I'll go ahead and file a bug report.