Improve the consistency between the weightEvents functions in LauSimpleFitModel and LauCPFitModel. Also remove the unecessary division by ASqMax in LauIsobarDynamics::getEventWeight.

git-svn-id: svn+ssh://phab.hepforge.org/source/laurasvn/trunk@533 30227d83-a2f9-49e9-9e98-657c83b2c86a