make rsyslog templates more dynamic:
- add config options for immark and imklog in rsyslog.conf.jinja, as the
formula provided template does
- add config options for imjournal, target/protocol, listentcp/listenudp
as the formula-provided template does
- enable imjournal for all machines
- set target/protocol for all machines apart from the syslog server role
- set listentcp only on the syslog server role