Add UpgradeInitCommand to deployed-server

Add UpgradeInitCommand to deployed-server

The commands specified by UpgradeInitCommand need to be run before
InstanceIdDeployment in deployed-server.yaml, otherwise the upgrades
hang with the resource in progress. This is because the new
python-heat-agent-apply-config has not yet been installed on the
deployed server.

Adding the UpgradeInitCommand (and corresponding
SoftwareConfig/SoftwareDeployment to apply it) will cause the new repos
and python-heat-agent-* rpm's to be installed before
InstanceIdDeployment.

An open question is whether or not Heat should even be triggering the
InstanceIdDepoyment to IN_PROGRESS on upgrade when only the group is
changing from os-apply-config to apply-config. If that turns out to be a
Heat bug, then this patch wouldn't be necessary.

Change-Id: I9d87f995744415b110a7d0bca8d2309d7167148c