- When processing input, check if there is any extra data
  pending in the internal websocket frame and SSL buffers.
- Prevents input events lagging behind because they get
  stuck in one of the buffers.
  Data pending in our own buffers cannot be detected with
  select() so was not processed until more input arrives
  from the network.
- Closes # 55
Signed-off-by: Floris Bos <bos@je-eigen-domein.nl>