adding PrecisionElectronRecoSequences.py which arranges reconstruction algorithms in sequence
This merge request introduces PrecisionElectronRecoSequences.py. The offline algorithms described in TrigElectronFactories.py are called in PrecisionElectronRecoSequences.py and arranged in the sequence of Precision Electron Reconstruction. Related JIRA https://its.cern.ch/jira/browse/ATR-18927. Adding @fernando , @tamartin , @tbold