Allow escaped characters in css selectors

[canvasplay]

Fixes autocomplete for css selectors with escaped characters as described here #288.
Currently only supporting the following escaped characters: \/, \@, \:

Fixes #288

[dziku86]

This doesn't works as expected (or I messed up copying n pasting your code 😴). Now it matches pseudo-classes/elements like .some-class:after and doesn't match classes with escaped characters at all.

[canvasplay]

Hello, sorry for long time inactive.
I fixed the error, now it does not parse unwanted pseudo selectors like :hover, :focus, etc..
Many thanks to @AeonFr helping with the regex.

[brochington]

@canvasplay Thank you for working on this!

Would it be possible to add an escape for .? I use a CSS class utility lib that is similar to tailwind, and has classes such as hrem-1\.5 for "height of 1.5rem". These classes are not detected by the extension.

[canvasplay]

Hi @brochington, if you don't mind, let's see first if @dziku86 want to merge this ;)

[canvasplay]

Any news on accepting this @dziku86?

[canvasplay]

Any news on accepting this @dziku86?

Alright! What the thumbs up really means? Are there any inconvenience on merging this PR? I think this is a good addition to the plugin and several people will benefit from it.

[dziku86]

Any news on accepting this @dziku86?

Alright! What the thumbs up really means? Are there any inconvenience on merging this PR? I think this is a good addition to the plugin and several people will benefit from it.

@canvasplay I don't have write access to merge pull requests 😕.

[canvasplay]

so @zignd, any chances to merge this? some people are interested on this addition.
Thanks in advance for your time!