Improve clipboard example program, fix compilation warnings.

Use show(argc,argv) to enable command line arguments and colors,
fix indentation, Windows compilation warnings, and change tab
selection color, which was too dark on my Win7 system (low
contrast with tab labels).

I also added #define TAB_COLOR to make changing the tab selection
colors easier, if needed.


git-svn-id: http://seriss.com/public/fltk/fltk/branches/branch-1.3@10318 ea41ed52-d2ee-0310-a9c1-e6b18d33e121