Shashlik DIGI-RECO

Working version of the shashlik DIGI-RECO

Changes Geometry and SIM:
 - Fix geometry by Ianna: shashlik geometry in CaloGeometryBuilder
 - Fix geometry by Fedor:  Shashlyk bug fix 3,  including Pull Request: #3957 
 - assert in preshower geometry initialization removed
 - Fix SIM parameters for shashlik from Sasha:
     - UseBirkLaw: True -> False (non linearity behaviour of the light yield w.r.t. energy loss)
     - UseWeight : True -> False (weigth for light collection of different fibers depending on the energy deposit position)
     - ReadOutType: 1 -> 0 (0 = 4 fibers combined, one readout)
     -  AttCorrection: True -> False 
   
DIGI:
  - EKDetId with hashedIndex
  - EcalPhaseIIDigiProducer: removed preshower digitization, added Shashlik
   - added Shashlik specific configurations and classes for electronics
   - Noise fixed at 0.3 ADC (2 MeV)
   - Digi are Zero Suppressed at 1 ADC count: for digi need unsuppressed digis around signal

RECO:
- Uncalibrated recHits and calibrated recHits added
- Particle Flow sequences added (check customization needed before)
- Fixed clustering 

  VALIDATION:
- Temporary removed some validations, still to be fixed (running without crashing)