Add activations test

test/utils/test_functions.cu

@@ -1,16 +0,0 @@
-#include <cuda_runtime_api.h>
-#include <driver_types.h>
-
-#include <iostream>
-
-#include "functions.cuh"
-#include "gtest/gtest.h"
-#include "test_cublas_fixture.cuh"
-
-class FunctionsTest : public CublasTestFixture {
-  protected:
-    cudaError_t    cudaStatus;
-    cublasStatus_t cublasStatus;
-};
-
-TEST_F(FunctionsTest, sigmoid) {}