Exclude `go-vet` and `go-test` from `goxc`
Exclude `go-vet` and `go-test` from `goxc`

There is an [goxc issue](https://github.com/laher/goxc/issues/90) that
say there won't be workarounds for missing vendoring support in `go vet`
and `go test`. To support building with goxc with vendoring we need to
disable this two tasks.
Related to #101

allegro/marathon-consul,guilhem/marathon-consul,trueanthem/marathon-consul,trueanthem/marathon-consul,allegro/marathon-consul,guilhem/marathon-consul