Handle Panel{SubType} types

[robotboy655]

Similar to table{} and number{} additions, I have added ability to mark the expected panel subtype via type="Panel{SubType}" syntax to the wiki.

Example:
https://wiki.facepunch.com/gmod/DScrollPanel:GetVBar

[luttje]

Awesome!

Given the backlog of issues and my currently limited free time I won't be working on this just yet. So if you've got time to make a PR that would be very much appreciated.

If you don't have time to make a PR I can make some time for this (and other issues) in about a month or so.