added photon lowmult lines in the ion sequence

• Added two lines: Hlt1PhotonLowMult and Hlt1DiPhotonLowMult
• These lines will be used for UPC diphoton analyses (pi0, eta, etc ...) including ALP searches
• Throughput decreased in pp is expected since the ADC thresholds are lower. This ADC reduction is necessary for lower pT photons.

Results Data Run 254507

|*"Selected by Hlt1HeavyIonPbPbMicroBiasDecision" |    100000 |          0 |( 0.000000 +- 0.000000)% |
|*"Selected by Hlt1HeavyIonPbPbPeripheralDecision"|    100000 |          3 |(0.003000000 +- 0.001732025)% |
|*"Selected by Hlt1HeavyIonPbPbUPCMBDecision"     |    100000 |      93084 |( 93.08400 +- 0.08023521)% |
|*"Selected by Hlt1HeavyIonPbPbUPCPhotonDecision" |    100000 |       2000 |( 2.000000 +- 0.04427189)% |
|*"Selected by Hlt1HeavyIonPbPbPhotonLowMultDecision"|    100000 |        585 |(0.5850000 +- 0.02411592)% |
|*"Selected by Hlt1HeavyIonPbPbPhotonLowMultFilterDecision"|    100000 |        577 |(0.5770000 +- 0.02395142)% |
|*"Selected by Hlt1HeavyIonPbPbDiPhotonLowMultFilterDecision"|    100000 |         20 |(0.02000000 +- 0.004471689)% |

Results MC ALP 3 GeV (generated without inAcc - expected ~7% with both photons reconstructed)

Hlt1HeavyIonPbPbPeripheral:                 0/100000, (    0.00 +/-     0.00) kHz
Hlt1HeavyIonPbPbCentral:                    0/100000, (    0.00 +/-     0.00) kHz
Hlt1HeavyIonPbPbUPCMB:                  26296/100000, ( 7888.80 +/-    41.76) kHz
Hlt1HeavyIonPbPbUPCPhoton:              99997/100000, (29999.10 +/-     0.52) kHz
Hlt1HeavyIonPbPbPhotonLowMult:          22236/100000, ( 6670.80 +/-    39.45) kHz
Hlt1HeavyIonPbPbDiPhotonLowMultFilter:   9222/100000, ( 2766.60 +/-    27.45) kHz
Hlt1HeavyIonPbPbPhotonLowMultFilter:    22229/100000, ( 6668.70 +/-    39.44) kHz