uninstallation script: fixes to make it ready for usage

[vilhelmprytz]

The uninstallation script created by @Linux123123 isn't fully ready to be used but was merged anyways into the master branch in #123.

These are the remaining things to fix:

• remove old Docker containers running
• remove old Let's Encrypt certificates

...that I can think of at least.

[Vondyy]

How do I uninstall this script?

[vilhelmprytz]

@Vondyy There is nothing with the script itself you can install/uninstall, but you can use the script to install Pterodactyl and hopefully (soon) you will be able to use the uninstallation script to uninstall it. Does that answer your question?