Fixed body timestamp conflict with default.

@bantherewind I'm pretty sure the issue I was experiencing was caused by a timestamp problem now. For instance, body tracking would only work if I set the framerate to <30fps.

For some reason, the new frame bodies would be tracked and added to the list but not copied over to mFrame. Essentially, this condition would fail: https://github.com/wieden-kennedy/Cinder-KCB2/blob/dev/src/Kinect2.cpp#L1148 Meaning, the default time stamp of the body update frame would be equal to the current one, so the inner body update would never be reached.

As a solution, I placed the default timestamp within the for-loop.

_I'm wondering if the timestamp logic could be removed. What about updating mFrame's components within each KCBIsFrameReady condition?_