A dial generator application

[nadrino]

As it was requested for the latest OA of T2K, the generation of event by event or binned dials (through splines) would be very usefull.

This dial generator would use the Propagator to generate effective and smooth response. Other apps like the fitter or the XsecCalc would use those for better performances or accomodate with their own constraints (like continuous gradient steps).