Officially support labels for pipelines and agents to improve pipeline picking.
* add pipeline labels
* update, improve docs and add migration
* update proto file
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closes#304 & #860
hotfix #717
This comes from the agent being inactive / not sending and requesting any data if there a no pipelines waiting for him to execute. GRPC seems to only allow 2 pings without calling an actual endpoint before closing the connection. I think this will be indirectly solved in the moment we implement something like #536https://github.com/grpc/grpc/blob/master/doc/keepalive.md
Co-authored-by: Anbraten <anton@ju60.de>