Add suspending capability for the minecraft server through the control
script and an additional screen session which listens on the same port
with netcat.
* Update .conf accordingly
* IDLE_SERVER can be either true or false
* The default is no idle server
* Choose an available netcat flavor automatically
Variable renaming in .install.
Notify the user of kept directories on post_remove and alter ownership
to root before removing the game user.
Print error messages to stderr.