[grapefruit] SystemMonitor

[Roman Cheplyaka]

I've added a new example -- system monitor[1]. Its intended behaviour is to
show average CPU usage in GTK text label.

However, when I execute main, nothing observable happens, looks like it falls
in an infinite recursion. Did I do something wrong?

Any criticism is appreciated, of course. I'll be in IRC later today.

I also pushed a small haddock fix, because the old haddock failed to be
parsed.

  1. http://code.haskell.org/grapefruit/main/grapefruit-examples/src/Examples/Grapefruit/SystemMonitor.hs
-- 
Roman I. Cheplyaka :: http://ro-che.info/
"Don't let school get in the way of your education." - Mark Twain