explicly create a shell using BRep_Builder in MakeShells.
explicly create a shell using BRep_Builder in MakeShells.

This includes a very ugly try-catch block as a workaround, so that all cases are handled correctly. This needs to be fixed!

addresses #403

DLR-SC/tigl,DLR-SC/tigl,DLR-SC/tigl,DLR-SC/tigl,DLR-SC/tigl,DLR-SC/tigl