[R-SIG-Mac] A few niggles with the new R interface

[hadley wickham]

I really like the new R interface (it's a vast improvement over
RAqua), but there are a few little niggles that I find rather
frustrating:

 * When restarting or shuting down the whole computer, R always
cancels the shut down process

 * R activity doesn't stop my computer from going to sleep

 * Sometimes when using cmd-` to rotate through active windows, all
the other windows are shuffled to the back of any other open
applications - this is frustrating when switching been help and code. 
However, this doesn't happen consistency, and I haven't been able to
figure out what triggers it.

 * help(package = "MASS") doesn't do anything

 * using stop (or pressing cmd-.) won't break out of a loop that uses try()

Hadley