Make a few statics const in CondFormats/JetMETObjects
Merge pull request #1425 from ktf/sr-CondFormats-JetMETObjects

Multithreading fixes -- Make a few statics const in CondFormats/JetMETObjects
Merge remote-tracking branch 'origin/CMSSW_7_0_X' into CMSSW_7_0_X