mtctl: A minetest server control command

Based on: systemctl (linux) and rcctl (openbsd)


# Usage: 

The mtctl is using the following pattern:

`$ mtctl <action> [worldname]`

* action: start|stop|restart|status|list|help
* worldname: worldname to control


# Install:

This script is easy to install, thanks to a one-line-installer. 

This installer will detect your OS and based on that info it will select which shell you have (and some other things)


The command itself is the following: 

`$ curl 'https://cvsweb.planetofnix.com/cgi-bin/cvsweb/~checkout~/mtctl/installer.sh?content-type=text/plain' 2> /dev/null | $SHELL`


# Setup worlds:

## For existing worlds:

Put your minetest.conf in your worlds/<yourworldname> as world.conf
Also specify the port in the world.conf 

## For new worlds:

Use $ mtctl create <worldname>
Or use the instruction for the existing worlds


# More info: 

* [Minetest Forums](https://forum.minetest.net/viewtopic.php?f=14&t=27093)