exclude nsf for now

Author: zuhengxu

src/NormalizingFlows.jl

@@ -129,7 +129,7 @@ end
 # interface of contructing common flow layers
 include("flows/utils.jl")
 include("flows/realnvp.jl")
-include("flows/neuralspline.jl")
+# include("flows/neuralspline.jl")
 
 export RealNVP_layer, realnvp