added workaround for gce for travis as per https://github.com/travis-ci/travis-ci/issues/7940
added workaround for gce for travis as per https://github.com/travis-ci/travis-ci/issues/7940

shirlei/helios-server,shirlei/helios-server,benadida/helios-server,shirlei/helios-server,benadida/helios-server,benadida/helios-server,shirlei/helios-server,shirlei/helios-server,benadida/helios-server,benadida/helios-server