Add quote icon

[Billiam]

• Name of the icon : quote
• Tags (alternative names for this icon) (add them in tags.json) : quotation
• What is the purpose of this icon? : Likely used as a button alongside bold/italic/strikethrough to indicate block quoting
• 100% scale preview :
• Have you considered alternative possibilities for its naming or design? : I tried a few versions with rounded tops and softer curves at the tip, but it ends up looking like a '99' very quickly. I think this is a good balance

I saw this was in the feather PR / issue list, and I needed it for my own project.

[Billiam]

Side note on the PR template:

• Unlike issue templates, you can't use named pull request templates without using a query string URL (ex: ?template=new-icon.md). I think you can use .github/pull_request_template.md if you don't need multiple templates, but it'll appear for everybody.
• YML metadata is ignored and just ends up in the issue body

[ericfennis]

@Billiam Thanks for opening, and welcome to the community.

I'm curious how it will look next to the other text editing icons.

[Billiam]

I'm curious how it will look next to the other text editing icons.

A bit like this. While it's not a great match for the text icons (since they're relatively thin and open), I think it fits in well with icons like 'image' and 'table'