Changing strategy to fix seldom blank screen

 * Previous fix has proved to be wrong: 0da4d73169b86dfa91e725bbb38ed58811499c7d
   changing the inter-thread synchronization by delaying the screen
   saver thread xlib job so that kdesk has time to create desktop
   icons and dispatch creation events.
Merge pull request #32 from KanoComputing/fix-freeze

Changing strategy to fix seldom blank screen