- added {truncate, round} as option to histograms
- added system message handling in exometer_proc
- removed exo from deps (not used)
- bug fix in exometer_folsom_monitor
- exometer_report:reporter_pids() return only valid pids
- fix corner case when fetching highest values for histogram
remove unused local function
Merge pull request #96 from Feuerlabs/uw-histogram-fixes

various fixes to histogram, exometer_report and folsom_monitor