(systemd service descriptions that is, not service descriptions in "man
configuration.nix".)
Capitalizing each word in the description seems to be the accepted
standard.
Also shorten these descriptions:
* "Munin node, the agent process" => "Munin Node"
* "Planet Venus, an awesome ‘river of news’ feed reader" => "Planet Venus Feed Reader"
Twisted provides option to log with syslog, this enables nicer logging.
Imagine what happens in a case of exception. If logs are written to stdout,
traceback won't be merged thus giving ugly logs. This commit fixes that.
This is also one of the official ways of starting carbon, so no worries.