* Fix improper indentations made obvious by the widen viewport
* Fix minor grammar issues
+ Add installation for nightly build using dotnet CLI

License @ https://github.com/ovasquez

- Reword TypeReader comment to avoid giving the idea that the sample itself is "obsolete"
- Remove CommandException logging comment regarding C#7.0 as the version is now the standard across VS2017 and up
- Remove suggestion about handling result in command handler since it is now advised to use CommandExecuted instead
+ Add additional comment to clarify ctor for DI setup

* Change paragraph, code, heading fonts
* Widen viewport

line 35 was _database.GetData() instead of DBService.GetData()

* Add webhook url overload for DiscordWebhookClient

Adds an overloaded constructor for `DiscordWebhookClient` which accepts the webhook URL. This URL is parsed using a regex for the id and token. If the token is invalid an `ArgumentException` is thrown.

* add null or whitespace check

* add some tests for the new DiscordWebhookClient constructor

* make the Regex static, specify flags

* update regex to look for "discordapp"

* specify reason why exception is thrown despite regex match

* move parsing logic into new function for testing

* Fix #1270 Add the AuthorId to MessageDeleteAuditLogData

Fix #1270

Adds the AuthorId property to MessageDeleteAuditLogData, which is set
by the TargetId in the audit log entry data.
This property is the user id that created those messages in the first place.
I am not aware of an instance of when this value would not be supplied.

* Adjust xmldoc wording

* add News channel type

* remove (very outdated) todo

* add [Socket/Rest]NewsChannel types

* update TextChannel properties to include a Type optional parameter with validation

as of writing, this feature is still only available to verified guilds, which makes it impossible for testing.

* actually create the news channels when given the type

* throw NotSupportedException in News channel

throw a NotSupportedException whenever trying to use SlowModeInterval or anything related to overwrite permissions

* make RestNewsChannel throw NotSupportedException also

* remove the (untested) ability to change channel types

bon voyage

* Fix NullReferenceException when the webhook was deleted

* Fixing doc note

* Better documentation regarding the webhook object

Co-Authored-By: SubZero0 <pnmanjos@hotmail.com>

* Clarify command samples by adding additional notes about each methods

* Add additional notes for the Program class

* Change wording on token read

* Change prefix sample to match referenced example

Co-Authored-By: Still34 <341464@gmail.com>

After talking at the Discord.Net channel, @Quahu stated the `member` prop doesn't contain the `user` in this payload (and it's described as being a partial at https://discordapp.com/developers/docs/resources/channel#message-object).

I completed it using the `author` prop, that I believe it's the cleanest way of dealing with it (without changing the GuildMember class or the AddOrUpdateUser method).

Solves #1267

* Use a relative path for docs index page logo

Changes the paths for the logo on the index page of the documentation
to use relative links instead of absolute ones.

The current absolute path is just fine as long as the site
is not hosted under another directory. When opening files locally
(without serving them in docfx) these images will fail to load.
In addition, if these files are served under a directory that is
not the root endpoint (like: `docs.com/stable/`) the images will
also break.

I tested these changes locally using these steps:

- Build & serve docs: `docfx docs/docfx.json --serve`
- Verify that logo shows up on index page using all 3 themes
- Open `docs/_site/index.html`
- Verify logo works on all 3 themes

* Minor grammar fix in DiscordSocketClient