TAE for HLT2 and monitoring improvements

TAE:

• Take RawData for central TAE crossing if not in Banks directory
• TAE events take trigger mask from central HltRoutingBits

Monitoring:

• Remove hacky dependency on Gaudi ROOT Sink
• Support Gaudi histograms created after start
  • Avoid JSON conversion during start (moving it to the first serialization).
  • The first serialization costs 2x JSON conversions.
• Prepare for Gaudi!1574
• Do not call MonitoringSvc::update on stop (done in !1006 (merged))
• Fix counter/histos with duplicated names
• Leading slash in histogram name means absolute path
• Remove unused member