Update documentation for xtract_lnorm()
Update documentation for xtract_lnorm()

kecsap/LibXtract,eriser/LibXtract,jamiebullock/LibXtract,jamiebullock/LibXtract,eriser/LibXtract,caseybasichis/LibXtract,caseybasichis/LibXtract,kecsap/LibXtract,kecsap/LibXtract,eriser/LibXtract,jamiebullock/LibXtract,caseybasichis/LibXtract