Added Element extension with .matches and .closest

What does this MR do?

This adds .matches and .closest polyfills that will help when removing/not using jQuery. I added these in another MR which was then refactored to not require these methods, but I thought we might as well not lose the code.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Help when removing/not using jQuery.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?