video.upload loads entire video file into memory

[thenewguy]

@https://github.com/sciyoshi/pyfacebook/blob/master/facebook/__init__.py#L1138

It appears that VideoProxy.upload() was copied from PhotosProxy.upload(). The upload method loads the entire file into memory. Seeing as to how high quality videos are quite large, this should be reworked in the VideoProxy for sure and arguably PhotosProxy as well for the sake of shared hosting or situations where memory is limited.