Tweaks to get end to end deployment working

WIP: Fourth round of refactoring for Manager

Fix repo prefix searchbug

fix(manager): add test for getDeployments*

feat(deployment): add describe command to helm cli

fix(validate-go): show the errors gofmt found

Repo name routes, tests and cleanups

Factor expansion service logic as an auxiliary library

fix(manager): add test for listDeploymentsRequestHandler

Rather than just listing files that have errors, this now shows
the diff of what gofmt things should be the case, and what is
the case.

doc(cli): improve help output