feat(installer): rewrite install script

- remove unused root packages.ini
- write config to yaml file
- allow to set public_url during install
- force icecast start right after package install
- move config file in place at the end of installation

BREAKING CHANGE: The bash installer has been rewritten, the flags and
options changed, please run `./install --help` to get more details.

api/install/systemd/libretime-api.service

@@ -6,8 +6,8 @@ Type=notify
 KillMode=mixed
 PrivateTmp=true
 
-Environment=LIBRETIME_LOG_FILEPATH=/var/log/libretime/api.log
-Environment=LIBRETIME_CONFIG_FILEPATH=/etc/libretime/config.yml
+Environment=LIBRETIME_LOG_FILEPATH=@@LOG_DIR@@/api.log
+Environment=LIBRETIME_CONFIG_FILEPATH=@@CONFIG_FILEPATH@@
 
 ExecStart=/usr/bin/gunicorn \
         --workers 4 \