DQMStore: fix the syntax used to forward calls from IBooker to DQMStore
DQMStore: forward more book calls from IBooker to DQMStore
Merge pull request #2013 from fwyzard/IBooker_variadic_calls_v2

DQM fixes -- automatically support all DQMStore book* calls in the IBooker (v2)
Merge remote branch 'origin/CMSSW_7_0_X' into CMSSW_7_0_X