* Update deps, fix test warnings.

* Support ns2.0

* Fix typo

* Remove ns1.1 support

* Net.Http and Net.Websockets.Client are not needed in ns2.0

* Move to net46 per volt

* Remove ns1.3 constants

* Implement DeleteMessageAsync

* Refer to MessageHelper instead of duplicating call

* Fix refactor error

commit 07bca5b31a
Author: Joe4evr <jii.geugten@gmail.com>
Date:   Fri Apr 6 09:44:50 2018 +0200

    Add ability to specify parameters on channel creation

commit 114e5b431b
Author: HelpfulStranger999 <helpfulstranger999@gmail.com>
Date:   Sat Apr 28 19:08:35 2018 -0500

    Fixes lack of default value for tts

commit 1fd8c70c53
Author: HelpfulStranger999 <helpfulstranger999@gmail.com>
Date:   Sat Apr 28 15:21:11 2018 -0500

    Makes text parameter of sending messages optional

* Cleaned up and refactored slightly

* Resolves #971

* Adds support for default avatars and resolves #971

* Amendment

* Final amendment

* Paginating reactions

* Amendments based on feedback

* Further amendment based on review

* Final(?) amendment

* Removes default limit and after user id

* Removes fromUserId; cleans up model creation; replaces function with individual parameters

* Copy audit logs impl from old branch and clean up

I suck at using git, so I'm gonna use brute force.

* Remove unnecessary TODOs

Category channels do not provide any new information, and the other
I forgot to remove beforehand

* Add invite update data, clean up after feedback

* Remove TODOs, add WebhookType enum for future use

WebhookType is a future-use type, as currently audit logs are the only
thing which may return it.

- Because DocFX sucks at rendering langword

* Initial support for invite member count arg

* Fix IDiscordClient#GetInviteAsync behavior

- Previously, the GetInviteAsync method would return null since it couldn't be parsed as a simple RestInvite object. The object should be a RestInviteMetadata instead.

* Fix methods that didn't comply with the interface

* Change with_counts REST behaviour

* Remove unnecessary JSON prop

* Remove AcceptAsync

* Add EditorConfig

* Add basic .NET style rules

* Add naming rules

* Add some more extension

* Add target of the internal fields

* Fix build fails when built on macOS and Linux

* Use 'Condition' attributes

refs: 6f29dda78b (r181371650)

* added UserDefaultAvatar to IUser

* pass ushort as discriminator

* removed unneeded ushort.parse

* Throw when attempting to modify a message not made by the current user

* Didn't realize the client is passed into the MessageHelper function

* Respond to feedback

* Fix comments to comply with third-person commenting style
+ Various attributes
+ Various Command-related objects
+ Many more

+ ActivityType
+ IAttachment
+ ChannelPermission
+ ChannelPermissions
+ ChannelType
+ Attachment

This resolves #987

Previous behavior was that even if `null` was passed for an embed in
UploadFileAsync, the Embed property on UploadFileArgs was still
specified - this meant we were always sending a payload_json.

If a payload_json is specified, it seems like Discord will only read
from the payload_json, and will ignore properties set outside of it.

To prevent unnecessary code duplication, this commit always specifies
parameters in the payload_json, and also will only include the embed if
one was actually specified with real data (not null).

* UnixTimestampConverter should now obey a maximum value

This change prevents an issue where the converter would be unable to
handle obscenely large timestamp values - which are actually quite
common on Discord.

OptionalConverter had to be rewritten to support checking whether or not
an InnerConverter returned an Optional. The perf impacts from this
_shouldn't_ be too bad, as types without a custom parser (which should
be the majority of Optionals in the lib) will bypass the type-check.

* optimizations on OptionalConverter