Latest release points at 2.0.7

[bradfordboyle]

Following the README, uploading the latest release gives 2.0.7 and not 2.1.0.

→ bosh2 upload-release https://storage.googleapis.com/bosh-gcp/beta/stackdriver-tools/latest.tgz
...
→ bosh releases | grep stackdriver
stackdriver-tools	2.0.7* 	6760188+

In 2.0.7, the agent config tries to load the application credentials from the nozzle job: https://github.com/cloudfoundry-community/stackdriver-tools/blob/2712c2c77c205fd84f8ade9b8bf8974a04a744dc/jobs/stackdriver-agent/templates/collectd-gcm.conf.tmpl#L61