Give sane defaults to some app confiugrations and allow apps to be POST created\updated without them being mandatory declared

[naorlivne]

Expected/Wanted Behavior

When sending a POST app creation\update the following fields should be optional and if not declared in the body of the request should recieve their sane default value:

• "starting_ports": [],
• "containers_per": {"server": 1},
• "env_vars": {},
• "running": true,
• "volumes": [],
• "networks": ["nebula", "bridge"],
• "devices": [],
• "privileged": false,
• "rolling_restart": false

Actual Behavior

All fields are currently mandatory when creating a new app or POST updating an existing one

[naorlivne]

added in latest, will be added to the next version release.