Now GTextEditor manages its own editing actions (cut/copy/paste/etc) and
will show a context menu containing them when requested.
Apps that want to put a GTextEditor's actions in its menu can get to the
actions via public getters. :^)
In order to move the WindowServer to userspace, I have to eliminate its
dependence on system call facilities. The communication channel with each
client needs to be message-based in both directions.
