This is a complete redesign of the old voice code.
A list of major changes is as follows:
* The voice websocket will now automatically reconnect with
exponential back-off just like the regular Client does.
* Removal of the stream player concept.
* Audio now gracefully pauses and resumes when a disconnect is found.
* Introduce a discord.AudioSource concept to abstract streams
* Flatten previous stream player functionality with the
VoiceClient, e.g. player.stop() is now voice_client.stop()
* With the above re-coupling this means you no longer have to
store players anywhere.
* The after function now requires a single parameter, the error,
if any existed. This will typically be None.
A lot of this design is experimental.
This is a breaking change. Move these two to TextChannel since the
other things that implement Messageable cannot reliably do bulk delete
actions in their respective channels.
The bug was due to the fact that the way overwrites work is by doing
a loop of all the values and then applying deny first and then allow.
That way the overwrite is defined if role A and role B deny a
permission but role C allows it (and said member has A, B, C roles)
then the resolution should allow it rather than deny it regardless of
the order of the data it is received in.
The permissions_for assumed that the everyone role would be the first
element of the permission overwrites but this is not guaranteed so we
have to guarantee it ourselves.
Rapptz