safer regex to match yt links

[Fusselwurm]

After the last update, this plugin started to match all sorts of URLs.

I propose a more restrictive regex:

regex	meaning
/<a href="http
s?	https is optional
:\/\/	end scheme, start domain part of URL
(?:[^\/]+\.)?	optional sub domains, non-matching group
`(?:youtube.com	youtu.be)`
\/	start path
(?:watch)?	optional group
(?:\?v=)?	forward to v=, if it exists
([A-Za-z0-9]+)	get the video id
[^"]*"[^<]*<\/a>/g	rest of the html href attribute, end of href attribute closing tag

[Fusselwurm]

(scratch that, its still retarded)

[Fusselwurm]

https://github.com/Fusselwurm/nodebb-plugin-youtube-lite/tree/jasmine