Added the ability to add nicknames for users

[apa420]

Pull request checklist:

• CHANGELOG.md was updated, if applicable

Description

Alias for usernames in twitch chat.

Closes #137

[talneoran]

Seems to work so far, some general notes:

• In terms of naming, I'm wondering if "alias" is the best option for users, as opposed to something like "nickname". I'm fine with alias but wondering what others think.
• I think something like this should be controllable through the usercard, like how the similar BTTV feature works. Maybe a usercard button that allows to add or edit your alias for that user. I suppose this could also be implemented on its own after this is merged though.

[apa420]

I think something like this should be controllable through the usercard, like how the similar BTTV feature works. Maybe a usercard button that allows to add or edit your alias for that user. I suppose this could also be implemented on its own after this is merged though.

I'm only doing a base implementation and am honestly not sure if it's worth implementing such a feature in the first place since it's a lot of work for little gain since it only adds a tiny convenience for a feature you'll probably rarely use (at least the way I see it).

You can even press the copy username button in the usercard to get the username.

[Mm2PL]

Here are some things I found in the code. One behvior I find weird is that @-s aren't transformed to use aliases, but that can be added later in another small PR.

[apa420]

To explain a bit about my alias implementation.
I personally would only want alias in the most simple sense possible, the name of the chatter gets changed from one name to another client sided.
For example my friend Che has the username just_che on twitch and I'd like it to just display Che for me personally and I don't really care about auto completing it or anything else.

Making the names actual aliases in the code would mean we'd have to separate aliases and normal usernames and you'll get issues where someone sets the alias to a user that already exists and it feels like it's such a mess for features most people simply won't use.

Searching with user: auto completion etc won't work with this pr nor do I think the feature should support it.

[gempir]

The highlights menu uses the terminology "Username" instead of "Name" so I think the column name here should be adjusted

[pajlada]

The highlights menu uses the terminology "Username" instead of "Name" so I think the column name here should be adjusted

Fixed