Use a fork of go tool vet to fix mutli-package directories

[dnephin]

Fixes #351

Uses a govet fork with this patch dnephin/govet@4a96d43

This seems to fix the issue for me on the gotestyourself project.

[alecthomas]

:(

Unfortunate. Are you going to attempt to get this patch merged upstream?

[dnephin]

Ya, I'll try. Opened golang/go#22296 and https://go-review.googlesource.com/c/go/+/71170

[dnephin]

golang/go#22296 (comment)

It sounds like maybe this issue has been fixed as of go v1.9. We should be able to use go vet -shadow.

[dpastoor]

I think this may have broken gometalinter, at least on travis getting

WARNING: exec: "govet": executable file not found in $PATH

and looking around looks like other projects builds are failing as well.

example travis file: https://github.com/dpastoor/babylon/blob/master/.travis.yml

[dnephin]

You'll have to install the forked govet, which is automatically installed if you use gometalinter --install.

Alternatively you can configure gometalinter to use the standard go vet

{
  "Linters": {
    "vet": {
      "Command": "go tool vet"
    }
  }
}

[dpastoor]

kk testing now...

[dpastoor]

thanks for the tip - it works now 👍

[dpastoor]

for those that run into this PR just added

+ - gometalinter --install
  - gometalinter --disable-all -E vet -E gofmt -E misspell -E ineffassign -E goimports -E deadcode --tests --vendor ./...

in the script section for travis