Add simple Tensor class

include/backend/backend.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <cstddef>
+
+namespace CUDANet::Backend
+{   
+
+class IBackend
+{
+public:
+
+    // Memory management
+    virtual void* allocate(size_t bytes) = 0;
+    virtual void deallocate(void* ptr) = 0;
+
+    virtual void copyToDevice(void* devicePtr, const void* hostPtr, size_t bytes) = 0;
+    virtual void copyToHost(void* hostPtr, const void* devicePtr, size_t bytes) = 0;
+
+};
+
+} // namespace CUDANet::Backend