Update docs for BETA19.
Update docs for BETA19.

scullxbones/metrics-scala,mnuessler/metrics,fcrepo4-archive/metrics,mveitas/metrics,AltitudeDigital/metrics,timezra/metrics,ind9/metrics,infusionsoft/yammer-metrics,cirrus-dev/metrics,dropwizard/metrics,dropwizard/metrics,wickedshimmy/metrics-scala,Banno/metrics,gorzell/metrics,thelastpickle/metrics,mattnelson/metrics,ohr/metrics,chenxianghua2014/metrics,ChetnaChaudhari/metrics,mtakaki/metrics,gburton1/metrics,erikvanoosten/metrics-scala,gorzell/metrics,infusionsoft/yammer-metrics,tempredirect/metrics,jasw/metrics,egymgmbh/metrics,gorzell/metrics,slovdahl/metrics,mspiegel/metrics,dropwizard/metrics,mt0803/metrics,signalfx/metrics,slachiewicz/metrics,mveitas/metrics,randomstatistic/metrics,fcrepo4-archive/metrics,gburton1/metrics,unitsofmeasurement/metrics,bentatham/metrics,jplock/metrics,wfxiang08/metrics,maciej/metrics-scala,valery1707/dropwizard-metrics,kevintvh/metrics,rexren/metrics