Don't decrease counter value on context manager exit.
Don't decrease counter value on context manager exit.

statsd counters are of a special type which is aggregated, sampled and
calculated into rate so decreasing those will result in invalid /
unexpected values.

Decreasing them would only make sense if statsd wouldn't do any
processing on them and treat them as raw values (e.g. gauges).

StackStorm/st2,Plexxi/st2,StackStorm/st2,nzlosh/st2,nzlosh/st2,nzlosh/st2,StackStorm/st2,Plexxi/st2,Plexxi/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2