Fixes issue #28

* The documentation for -graphite says to use - to disable, this
  implements that functionality.
support for -ve counters including test coverage of re-written processCounters()
fixes #19
Merge pull request #37 from losinggeneration/fix_issue_28

Fixes issue #28
tidied up with `go fmt`
add test and distribution scripts
"fix" some command argument help text

flush-intervals, received, percent-threshold is percentile
Merge pull request #44 from ploxiln/arg_help_spelling

"fix" some command argument help text
Merge pull request #42 from jehiah/test_dist_scripts_42

release scripts
Merge pull request #41 from JamesCohen-awin/negative-counters

support for -ve counters
improve handling of malformed data
fixes #45
Simplified tests:

 - using known UNIX timestamps to remove regexps and make assertions clearer
 - removed extra testing/dependency on parseMessage() in mean/% tests
Merge pull request #46 from JamesCohen-awin/issue-45

improve handling of malformed data
Merge pull request #47 from JamesCohen-awin/test-tidyup

Simplified tests
Relative gauges