* Changed the path from 'lastmodified' to 'last-modified' for consistency

* Moved theme-switcher code to scripts partial file
+ Add author's MIT license to featherlight javascript

* InvalidPathChars does not exist in NS1.3; replaced with GetInvalidPathChars instead.

+ Add precondition usage sample
+ Add precondition group usage sample
+ Move precondition samples to its own sample folder

+ Fix various formatting.
+ Provide a more detailed walkthrough for dependency injection.
+ Add C# note at intro.

* ConnectAsync(bool external) API implemented

This allows developers to handle the AudioClient externally (for example with Lavalink)

* Modify ConnectAsync API and add DisconnectAsync to IAudioChannel

* Update summary message on IAudioChannel.DisconnectAsync()

* Review changes:
- Fix `if (!external)` styling
- Remove unecessary ConnectAsync overload

* SocketVoiceChannel overload update

* Update IAudioChannel.ConnectAsync()
- Remove ConfigAction from parameters
- Add SelfDeafen/SelfMute to parameters

* Remove SocketVoiceChannel.ConnectAsync() default params (Inherit)

some guilds aren't on g250k yet? not sure

Forgot to hit save properly... Whoops.

Closes #1074

This code was not referenced anywhere in the active codebase.

Use (actual, expected) format for Assert.Equal, fixes analyzer warnings

Discord no longer treats channels prefixed with 'nsfw' as NSFW,
so we no longer need to have this check.

This reverts commit adf4da19fc.

Someone hasn't written c# in a while

Improve XML docs for commands quotation mark aliases feature

* fix channel permissions modify parameter to use nullable boolean, correct default value

* Add general tests for the ChannelPermissions.Modify method to test default values

* remove unused cast in tests

* add guildpermission modify no param tests

* Add no-param modify tests for OverwritePermissions

* fix inconsistent parameters in GuildPermissions cstr

* Adjust formatting of methods and cstrs with many parameters

* remove temp file that was included. no idea what that is

* Fix System dependency

I should really stop fixing merge conflicts in the github website.