fixed segfault when loading python wrapper. added mac support for python wrapper.
fixed segfault when loading python wrapper. added mac support for python wrapper.

DLR-SC/tixi,melven/tixi,DLR-SC/tixi,melven/tixi,melven/tixi,melven/tixi,DLR-SC/tixi,melven/tixi,DLR-SC/tixi,DLR-SC/tixi