[Clojure] Add helper function to convert formed vector to NDArray (infers shape)

[gigasquid]

We have a ndarray function called array that will take a 1d clojure vector and a shape vector and turn it into a ndarray. The Scala function has a new helper function that allows you to pass in a dimensional float/double array and have the NDArray create it and infer the shape.

It would be nice to create an interop function for this.
Example of interop:

user=> (def x [[1.0 2.0 3.0] [4.0 5.0 6.0]])
#'user/x
user=> (NDArray/toNDArray (to-array (mapv #(to-array %) x)) nil)
#object[org.apache.mxnet.NDArray 0x382169db "[\n [1.0,2.0,3.0]\n [4.0,5.0,6.0]\n]\n<NDArray (2,3) cpu(0) float64>"]
user=> 

[mxnet-label-bot]

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[Chouffe]

Should we close the issue now @gigasquid @kedarbellare?