Added DiElectron High Mass lines

This is a draft for HLT1 dielectron triggers which cover the mass range of the Upsilon and higher. At some point, at about 15-20 GeV, these should overlap quite a bit with the SingleHighPtElectron line, so its exclusive rate is particularly manageable. Covering the Upsilon can allow for plenty of calibration around those peaks, where we have to deal with more energy loss.

A rate test indicates the exclusive rate wouldn't affect our data taking:

Line:	 Hlt1DiElectronHighMassDecision                           	 Incl:   12.0 +/-   5.99 kHz,	Excl:    0.0 +/-   0.0 kHz
Line:	 Hlt1DiElectronHighMass_SameSignDecision                  	 Incl:    6.0 +/-   4.24 kHz,	Excl:    0.0 +/-   0.0 kHz

Right now there's pT and p cuts included, similar to those of the Drell-Yan lines:

• p > 14 GeV
• pT > 1.5 GeV
• m between 8.0 and 140 GeV All these are computed after bremsstrahlung correction.

On Upsilon(1S) signal, with a lower mu and the VELO partially open:

Line:	 Hlt1DiElectronHighMassDecision                           	 Incl:  4242.0 +/- 70.024 kHz,	Excl:  1258.7 +/- 40.292 kHz
Line:	 Hlt1DiElectronHighMass_SameSignDecision                  	 Incl:    18.8 +/-  5.035 kHz,	Excl:     4.0 +/-  2.331 kHz

@hyin