PCT-734: GOPATH can have multiple paths
Let's use same detection as in percona-agent:
https://github.com/percona/percona-agent/blob/3a24d7c9f08dc635d65646fb8912a85ae5abd1ff/test/app.go#L39
Merge pull request #2 from percona/PCT-734_gopath_can_have_multiple_paths

PCT-734: GOPATH can have multiple paths