Parameterize GitHub org and team settings

[fricklerhandwerk]

As a contributor, in my development shell I want to conveniently override application settings, such as the org and teams to sync with.

Currently one can't run the service locally without manually changing the GitHub parameters, or manually create a USER_SETTINGS_FILE. There is a way to generate that file programmatically which is accessible to the module.

Extract that functionality into a helper script that is available in the devshell and will create the right thing from an untracked directory, e.g.

.settings
├── GH_COMMITTERS_TEAM
├── GH_ORGANIZATION
└── GH_SECURITY_TEAM