Adds some info about backup and restore.

Signed-off-by: Markus Hubig <mhubig@gmail.com>
Renames the nginx server name to docs.

Signed-off-by: Markus Hubig <mhubig@gmail.com>
Adds a line to the pg_hba file for every database.

This is needed since they updated the image entrypoint script ...

Signed-off-by: Markus Hubig <mhubig@gmail.com>