At this moment, we only support running mysql server inside the
container. Support for running mysql(and memcached) in a separate
container would be added later.
shared/seafile => contains ccnet/seafile-data/conf etc.
shared/db => contains mysql data
shared/ssl => letsencrypt certs
shared/logs/seafile => ccnet/seafile/seahub logs
shared/logs/var-log => mounted as /var/log in the container