* Change GuildMemberUpdatedEventArgs to contain before and after DiscordMember objects (#1359)

* Fix #1325 - WebhookBuilder Throws Bad Request (#1363)

* use DiscordMentions on RestWebhookPayloads

* keep null value when null

* remove null check from discordmentions arg

* Implemented PATCH /guilds/:guild_id/roles (tested) (#1311)

* Fix compile errors caused by #1333

* Update hosting.md

* Remove unused DSharpPlus.MSTest folder

* Cache threads upon thread creation (#1366)

* categorization for the cnext default help command (#1371)

* Fix memberBefore missing roles in GuildMemberUpdateEventArgs when not… (#1364)

* Fix memberBefore missing roles in GuildMemberUpdateEventArgs when not in cache

* Update cached guild member in OnGuildMemberUpdateEventAsync internal event handler

* Update DiscordClient.Dispatch.cs

Co-authored-by: Lunar Starstrum <lunar@forsaken-borders.net>

* Ported CommandsNext cooldown attribute to Slash Commands (#1375)

* Ported CommandsNext cooldown attribute to Slash Commands; Fixed compiler warnings and suggestions

* Still untested; Attempted to resolve @Erisa's review

* Made all exceptions inherit from ApplicationCommandExecutionChecksFailedException (previously Exception)

* Start on converters

* Added custom converter support:

- No, I did not implement the checks in the converters. I felt that should be done in a separate area of code
- Yes, I did break my Enter, Backspace, D and Apostrophe keys because of this PR. Don't ask how.

* Fixed startup errors; Added DiscordMessageArgumentConverter; Added (un)register converter methods (untested).

* Fix registering converters

* (untested) Add number converters; Fix enums not registering choices correctly

* Add DiscordMember converter; Switch from ArgumentException to new MissingArgumentConverterException

* Actually fix Nullable and update TimeSpan converter to match with CNext

* Add params/array support

* Boundry checks

* [ci-skip] Resolve naming errors

* "One less variable allocation"

* Remove unsupport NETSTANDARD1_3 support; Un-Emziware those variable names

* Remove unused property

* Extra parameter limit attribute check

* Remove UnregisterConverter(s) methods

* Changed BCL types to use framework names

* Pass InnerException to prevent passing TargetInvocationException

* Fix enum support (again)

---------

Co-authored-by: Bob Loblaw <razvanmandache@gmail.com>
Co-authored-by: waffle-lord <76401815+waffle-lord@users.noreply.github.com>
Co-authored-by: Iris Féanorá <61018569+ExaInsanity@users.noreply.github.com>

… load of NOT MY PROBLEM. (#1333)