New 3 si pixel2 d template db object - targeting 73X

The AlCaDB meeting has approved, targeting 73X
Automatically ported from CMSSW_7_2_X #5218
Sorry, this got overlooked with the workshop and other things keeping us busy ... :(

Do you really need 1M elements here in this vector ???
Also, you never check in the code below if you are within that limit.