you can now open/close the console independently of menu and messagemode

you can now open/close the console independently of menu and messagemode
console catchs input before anything else
console appears ontop of anything else
console is no longer forced fullscreen when there is nothing else to show
shuffled around the 2D drawing calls in CL_UpdateScreen
now only console pauses singleplayer, instead of console/menu/messagemode
simplified console singleplayer pausing code a bit
mouse grabbing is now only forced off when console is down, not when menu or messagemode is shown

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@2327 d7cf8633-e32d-0410-b094-e92efae38249