* Add Webhook API models, REST implementation, and Socket bridges.

* Remove token overrides from REST.

Leaving that as a Webhook package only feature.

* Add Webhook API models, REST implementation, and Socket bridges.

* Remove token overrides from REST.

Leaving that as a Webhook package only feature.

* Webhook core implementation.

* Webhook REST implementation.

* Webhook client implementation.

* Add channel bucket id.

* Add BaseDiscordClient. Add various missing RequestOptions args.

DiscordSocketClient and DiscordShardedClient's shared members now exist in this abstract class.

* Add ShardReady event.

* Style consistency. Remove extraneous overloads.

Remove extraneous overloads.

* Add BaseSocketClient#DownloadUsersAsync().

Style cleanups.

* Add ShardLatencyUpdated event.

Style cleanup.

* Hook LatencyUpdated for ShardedClient.

* Begone whitespace.

* I'm good at this, I swear. >_>

* Add back DiscordShardedClient.UserPresenceUpdated

* Add ObsoleteAttribute

* Removing the UserPresenceUpdated event.