aria-invalid grammar and apelling support

[vincebanzon]

Hello, I'm new here and I really want to help this project. In fact, I started this project myself a year ago.
Better to support this project instead.

Anyways, I see the <input> tag uses aria-invalid. We currently have Valid, Invalid, Disabled which has colors green, red, and gray respectively.
Though, we don't have YELLOW for warning. Can we add yellow?
For starters, we can support yellow for aria-invalid="spelling" or aria-invalid="grammar"

Reference: aria-invalid