*read 32 bit event ID from GT/EVM or emulator FED
*single-buffer mode fix for case when header does not fit
* variable to switch between using L1 and GTP event ID
* fake EVM event ID record in fed generator
Merge pull request #4885 from smorovic/gt-event-id-72

Reading event id from EVM FED
Merge remote branch 'origin/CMSSW_7_2_X' into CMSSW_7_0_X