1. DenseMatrixOpsExp: Added some cleanup code to emit a complete kernel
that is to be autotuned. Right now engaging C++ backend. Will explore
CUDA backend later on.
2. Nits:
        Need to emit correct result type in kernelHeader. Right now,
        it's a dummy "myResType". Not sure if emitting the correct
        result type is necessary, I don't care about the result unless I
        pass it through a verifier.

Next step is to similarly emit a driver function. Don't know if it makes
sense to emit a driver function or just use a static driver function template.
Some more thinking, next commit must be interesting