- add django settings module documentation
- use default for previously required fields
BREAKING CHANGE: The API command line interface require the
configuration file to be present. The default configuration file path is
`/etc/airtime/airtime.conf`
* feat(legacy): allow custom port for database connection
- fix heredoc for php72
* update test config db section
* update sample config db section
* update api db config
* use defaults for database config section
* update documentation
* more documentation for migration