RenderScript support ops for TensorFlow

Two most energy and time consumption ops on Android device.

• matmul_op
• conv_op

Please check out the document at page 15 of TensorFlow-RenderScript Doc.

• The test data was fetched from TensorFlow runtime data.
• NDK version>=r14
• No need to worry to the two error messages of matmul uint8_t test, I just too lazy to rewrite the correct reference output computation.

An integration with TF can be see here: TensorFlow-RenderScript.