RECO Step working for HGCal + Basic CMS PFlow Hooks

Built ontop of : CMSSW_6_2_X_SLHC_2014-06-04-0200

Includes #4029 from @vandreev11

Tested in 12200 and 12219.  

Right now there is a bug in the HGC geometry, all silicon cells are given coordinates (0,0,0) this causes the energy-in-MIPs when selecting hits to always be zero, resulting in an empty list of PFClusters since none are selected.

@pfs You might be interested in this!