Upgrade Ehcache to 2.5.2.
Upgrade Ehcache to 2.5.2.

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