patch applied (ghc): Add a -fghci-sandbox flag so that we can en/disable the ghci sandbox

[Ian Lynagh]

Fri Oct 15 10:27:46 PDT 2010  Ian Lynagh <igloo at earth.li>
  * Add a -fghci-sandbox flag so that we can en/disable the ghci sandbox
  It's on by default (which matches the previous behaviour).
  
  Motivation:
  GLUT on OS X needs to run on the main thread. If you
  try to use it from another thread then you just get a
  white rectangle rendered. For this, or anything else
  with such restrictions, you can turn the GHCi sandbox off
  and things will be run in the main thread.

    M ./compiler/main/DynFlags.hs -1 +4
    M ./compiler/main/InteractiveEval.hs -6 +13
    M ./docs/users_guide/flags.xml +6

View patch online:
http://darcs.haskell.org/cgi-bin/darcsweb.cgi?r=ghc;a=darcs_commitdiff;h=20101015172746-3fd76-7c9c2bf65a98c3933013a0bfb0f958eff170bfcc.gz