Fixed waiting without tox argument.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Fixed #12 Read timed out.

  The cause of this issue is in the post-processing of the open()
  when uploading a large file size. read() the file object.
  The requests module for support streaming upload, it was changed to use it.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>