Get travis build working to push docker image

[s1cyan]

Currently the travis build pushes the wrong contents into the docker image. Update it for the go swagger server

Also add in a lint step
Basically similar to what we did in command-line-services. Implement a lint step in travis to make sure that pushed code is ok
See: https://github.com/kabanero-io/kabanero-command-line/blob/master/Makefile