This introduces a "sidecar" container, which is meant to be used
besides other containers (or as part of the pod). It merely uses
rsyslog to listen on a specific UNIX socket and outputs what it
gets to stdout.
This adds the service to each relevant role and introduces a
composable service which merely configures the container. Subsequently
it'll be used as part of other templates.
Note that it is only enabled if "stdout logging" is enabled.
bp logging-stdout-rsyslog
Depends-On: I4864ddca223becd0a17f902729cf2e566df5e521
Change-Id: I2c54acaaa820961c936f1fbe304f42162f720496