add config (deleteIdleStats) to delete idle sets, gauges, timers - and a overall flag to set them all but allow individual overrides
    update delete_counters unit test to test deleteIdleStats which covers all stat types
update readme and example for deleteIdleStats and friends
reorder example for easier merge
reorder example for easier merge
update pr/232 to be merge-able
Merge pull request #269 from etsy/keen99-p/deleteidlestats

update to pull/232 Keen99 p/deleteidlestats