Setup a FOSSUnited Matrix server for public chat

@Nemo, if I am not mistaken, you cannot run your bridges on the matrix.org instance.

Also I had run a matrix instance for my friends group for a year and i can help if you face any issues! I highly recommend using the ansible playbook. If you need to host multiple serivices on that server, you can use your own nginx server instead of the one that comes with the playbook (which is what i did)!