Merge pull request #522 from kolia/tiny_stack_bugfix

Tiny bugfix: `stack` was still calling julia 0.6 `cat`

test/utils.jl

@@ -87,6 +87,12 @@ end
   @test size.(params(m)) == [(5, 10), (5, 5), (5,), (5,)]
 end
 
+@testset "Basic Stacking" begin
+  x = randn(3,3)
+  stacked = stack([x, x], 2)
+  @test size(stacked) == (3,2,3)
+end
+
 @testset "Precision" begin
   m = Chain(Dense(10, 5, relu), Dense(5, 2))
   x = rand(10)