GitLab

Bump testing to Python 3.5 and postgresql 9.5 (ubuntu xenial)

Small usability fixes for the execution inspect page
Move all the database access in the state package
Remove image management, it is too slow to download images before while the user waits the the ZApp to start
Make several thread loops more robust in case of uncaught exceptions

- remove executions with fatal errors form the scheduling queue
- set services to error state when they fatally fail starting
- re-implement log streaming that was not working

If activated, docker will be configured to send service logs to the zoe master, who will save them to disk. Then they can be streamed via the command line or the web interface.

Update also the port description