Build/test/golint/goimports on a push or pull request (blues#2)

* Build/test/golint/goimports on a push or pull request

* reduce number of go versions we build in CI

* lint and check code formatting before running tests

* Use staticcheck instead of golint

Change staticcheck install command

fix staticcheck command

* fail goimports if errors found

* only build on a push

* run staticcheck on all directories

* remove build step