* Allows `run_volume_tags` to be set without requiring a major rewrite
of the (common) amazon builder code used to start an instance.
The common start up code tags the instance and *all attached volumes
at creation*. If `run_volume_tags` are set this means that any volumes
specified in `ebs_volumes` will *initially* be tagged with the
`run_volume_tags` rather than the tags set in the `ebs_volumes`
section
* Once the instance is reported to be 'ready' the step to tag the EBS
volumes is run. Once complete all volumes should have the tags
requested by the user:
* Volumes associated with the source instance should be tagged with
the tags set in `run_volume_tags` (if any)
* Each EBS volumes specified in the `ebs_volumes` section of the
template should only be tagged with its associated tags (if any)
* Currently this results in *all* volumes attached to the instance
being tagged with the `run_volume_tags`. This includes any `ebs_volumes`
for which the user may have configured other tags.
* This issue will be addressed in a later commit
Without conflicting over the name of the launch template that they create/delete.
Previously, the launch template name was just hard coded to `packer-fleet-launch-template`, but since AWS enforces unique template names within an account, this caused simultaneously running packer instances to hit template-already-exists errors when creating their templates and race-conditions around deleting the template. Now, the template name is randomly generated on each run, so there should be no conflicts.
* I had to contextualise Communicator.Start and RemoteCmd.StartWithUi
NOTE: Communicator.Start starts a RemoteCmd but RemoteCmd.StartWithUi will run the cmd and wait for a return, so I renamed StartWithUi to RunWithUi so that the intent is clearer.
Ideally in the future RunWithUi will be named back to StartWithUi and the exit status or wait funcs of the command will allow to wait for a return. If you do so please read carrefully https://golang.org/pkg/os/exec/#Cmd.Stdout to avoid a deadlock
* cmd.ExitStatus to cmd.ExitStatus() is now blocking to avoid race conditions
* also had to simplify StartWithUi