Add new QEE HLT2 and Sprucing Lines to master

FYI @wbarter @lcalefic @ncooke @jideng @tmombach @fredi @lsestini @ausachov @cvazquez @hyin @dzuliani (tagging conveners, liaisons and those who contributed MRs to this effort, apologies if I missed anyone!)

This MR adds the following QEE-specific developments to master:

• Enables persistreco for all the QEE dilepton lines (!933 (merged))
• Adds an example Z->MuMu sprucing line (!853 (merged))
• Adds a copy of the Hlt2SingleHighPtMuonLine with no MuonID, appropriately prescaled (see !1000 (merged)),
• Modifies our di-jet HLT2 lines from 1->18 lines with differing thresholds and tags (!1001 (merged)),
• Adds a suite of HLT2 single high-pT electron lines (!1004 (merged)),
• Adds HLT2 lines for Z->ee and same-sign high-mass dielectron candidates (!855 (merged)),
• Adds sprucing lines for ttbar->electron+muon, and boson+jet (!1005 (merged) and !1321 (merged)),
• Migrates the HLT2 Z->MuMu lines to ThOr (!1374 (merged)),
• Adds diphoton HLT2 lines (!1171 (merged)),
• Prefer Hlt2Line over HltLine (!1355 (merged)) and book our lines separately for HLT2 and sprucing (!1386 (merged)),
• Adds di- and tri-jet sprucing lines (!1295 (merged)).

It also adds QEE-specific example options files, which can be removed and kept on a QEE-specific branch to avoid cluttering master if desired.

Most of the lines are not migrated to ThOr due to missing functors, which are all known and documented in various issues. All lines here that can be migrated at this time have been migrated.

Rates and efficiency information will be collated and posted in the description.