Hello, 

I Improved the distributionMap wizard on several points:

=> no long computations anyMore. Should be usable with large models

=> adding some 'conditions' before leaving the first pane. Avoid to end with exceptions:

         - if properties are not well entered

         - if properties specified are not 'computable' for this model

=> refactored/cleaned code/ Divided into shorter methods/recategorized

    Looks at least cleaner than before

It should fixe the problems recently experimented when trying all moose menus