changes for running on ppc64 with gccgo

I have a couple of changes for running the go bosh agent on Power8 Ubuntu LE. Please review.
stemcell building uses following `/var/vcap/bosh/bin/bosh-agent -I dummy -P dummy -M dummy &`. `-P` is used with `dummy` platform which should not start monit, since StartMonit() is empty. Given that there is no need to modify LinuxPlatform's `StartMonit()`.