Add handling of non-standard ports
The default port instantiated by the self-hosting system sues port 8080. There might be users who already use that port for something else. As such, this should allow for an easy set up for those users who might wish to use a different port. Please note that I was unable to test the caddy set up, as such it might not function correctly. However, this appears to work for nginx.
The nginx docker file is now the only edited docker file. Additionally, when using caddy the bash script will not ask for a custom port.
Due to the many changes to the installation process, this PR should probably be started from scratch if still desired.