Add barriers to the config file which allows the last chosen on/off setting to remain persistent between game sessions

[Koi-MC]

Yeah so it now saves your barrier setting between sessions using the config file. Feel free to give this a test. I haven't seen any issues with this implementation from my own testing, but of course check it and/or clean it up if needed

Basically all methods of swapping barrier on/off now write to config and load from config on game launch:

• Using the 'b' hotkey
• Using /visiblebarriers visibility barriers true/false
• Using /visiblebarriers settings visiblebarrier true/false

[AmyMialee]

i'll leave this for now but in the overhaul this will probably become the default way it works

[AmyMialee]

merge anyway because why not for now Plus it puts you in the github contributors list :)