New Ecal Local Reconstruction with Multifit

Adds additional EcalUncalibRecHitWorker for MultiFit (using Fast NNLS algorithm) and modifies appropriate sequences to activate it by default.

@argiro @emanueledimarco
Is anyone actually using these bits?
If they are useful, then shouldn't there be some support for the previous version?
As is, hits created with the old version of the code will have some irrelevant values.