Consolidate MeasurementProviders
- remove initialize,nominalZ from IMeasurementProvider (not needed)
- IMeasurementProvider::addToMeasurments: use range of LHCbIDs instead of vector of LHCbIDs
- increase interface version number of IMeasurementProvider
- replace VPMeasurementProvider with MeasurementProviderT
- streamline MeasurementProviderT, reduce duplication of code