GitLab

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

Add a field in the service description to specify the network on which the container should be attached

The driving idea is that nodes with less labels are more generic,
nodes with more labels are more specialized and should be used by
executions that do not have those labels only as a last resort

Tune the new scheduler policies: prefer hosts without labels and reset the size of execution in the queue to implement back-filling

Implement the DYNSIZE scheduler policy that automatically calculates a size and dynamically makes it smaller when the zapp is waiting in the queue