Add modulecmd support to rsyslogcustom

example modulecmd in rsyslog:
`<13>1 2014-04-01T11:41:31.151132+02:00 node107 modulecmd: - modulecmd::  Uvsc400xx Hnodexxx.gengar.os VCgengar VALharpertown ID444xxxx[xxx].master.gengar.gent.vsc bash_load_cluster@gengar`