Add method to get list of Output names. Intended use in scripting where the Output iterator is not accessible.
Add method to get list of Output names. Intended use in scripting where the Output iterator is not accessible.

opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core