initial changes for merging DQM histograms
DQM histogram merging working
indentation fix
ignore DQM stream in case fastHadd command test fails
Merge branch 'master' into dqmHistograms
Pid check before process stream files.
Add the notify thread stop on main exception
*modified mount parameter for output disk
*check if root dir before attempting delete
fixed test logprint central index query
avoid race with process watchdog
*restart on >0 exit code (it seems to be casted to unsigned char, e.g. _exit(-1) --> code 255 in python)
*introducing global lock to prevent simultaneous access
*preparation for central ES changes
cleaner error reporting and exit on inability to mount ramdisk or output
Merge branch 'dqmHistograms' into m+h

Conflicts:
	python/aUtils.py
fastHadd fix
histogram merging test file
*improved DQM histogram stream handling (removing files if lumisection was empty)
*zero events json file is copied to output for streamDQM and streamDQMHistograms to cover cases where no events were processed (this is needed for current lumi checks by DQM)
caveat: CMSSW processes might not see each lumisection, but this should be a very rare case
minidaq hosts will use runindex_minidaq central index name
different runindex also for dqm machines (currently hardcoded)
BoLS files created also for empty lumi for two DQM streams