[jitter] rtt,ctt and fbo example file crashes max 5

Sorry for the crash, and other issues with this patch.

First off, your graphics card doesn't support floating point data, so  
it's kind of moot. However for people whose graphics cards do support  
floating point data, I've added a jit.window display @size 8 8 @border  
0 for the next release to have an almost invisible context. This makes  
the patch load and work properly the first time on my machine. However  
I'm experiencing some issues with "jit.gl.texture: error entering  
unbind: GL Error: Invalid operation" after loading and closing the  
patch. We'll be investigating this issue.

Thanks,
Joshua