Use control/zeromq framework for communication between metamodelling services

[wvangeit]

To make communication more performant/reliable in meta-modelling, we should mostly rely on the following framework to do communications: https://github.com/ITISFoundation/osparc-control/

There already exist prototypes of this, but several issues have been identified:

### Tasks
- [ ] To create control sockets, the services need to know each other's address. The address is the name the user gives to the box of the service in the GUI
- [ ] If the name of the box of a service in the GUI has the wrong format, it can not be used as address for the control framework
- [ ] If the user change the name of the box of a service in the osparc web interface, while running a study, the network name of the service is unstable
- [ ] We need to define some kind of port mechanism for osparc study/service that define control ports
- [ ] We should make the osparc control framework usable for computational services
- [ ] The osparc web interface needs some way to visualize the control connections
- [ ] we probably want to integrate these control connections in some way in the api server
- [ ] investigate in how far control connections are possible between services in different zones/regions/continents etc
- [ ] investigate possible rate-limiting of these connections

[wvangeit]

FYI @sanderegg @pcrespov I'm creating this issue, to keep track of all the things we need to be able to use the control framework/zeromq in metamodelling

[wvangeit]

also FYI @bisgaard-itis, this could take some load away from the file server api :-)

[bisgaard-itis]

also FYI @bisgaard-itis, this could take some load away from the file server api :-)

Yep, sounds good. I would be happy to help out with this.