updated the geometry mapping dialog so it is more intuitive
Fixed compiler warning concerning initializer list sequence.

‘GeoOnMeshMappingDialog::_new_geo_name’ will be initialized after base ‘QDialog’.
Returning/Using const reference instead a copy of std::string.
Merge pull request #3 from TomFischer/GeoMappingOnMeshDialogUpdate

Fixed compiler warning concerning initializer list sequence.
added changes based on PR-comments
Merge pull request #266 from rinkk/GeoMappingOnMeshDialogUpdate

Geometry mapping dialog update