Added option whether to build TiGLViewer
Added option whether to build TiGLViewer

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