add unique tag for grok parser in module input

how are syslog input tests executed and where? because for the command "make test" the tests are excluded. when I executed them (setting :socket => false ) I get a jruby exception:

Exception in thread "Ruby-0-Thread-109: /Users/simon/Workspaces/logstash/lib/logstash/inputs/syslog.rb:89" org.jruby.exceptions.JumpException$BreakJump

I added a new tests for the tag and also improved a little bit the old one.