Add support for batch transfers

[pieths]

Currently, each return value is transferred from managed code to native code one at a time. See NativeDataInterop.cs.

for (int i = 0; i < fillers.Length; i++)
{
    fillers[i].Set();
}

...

_poker(value, _colIndex, _input.Position, 0);

Could performance be increased by batching the values and sending over a batch at a time? This would reduce the amount of managed/unmanaged transitions.