Thanks to jforman for finding this one, emerge was not helpful when permissions on...

Thanks to jforman for finding this one, emerge was not helpful when permissions on the world file are not so good, so in the case of permission denied, we reraise, essentially telling the user we can't read the world file.  In the case of it not existing, we assume the user knows what they are doing and we print a squelchable warning message.

svn path=/main/trunk/; revision=3089