Add ability to enable WebSocket support for curl (and maybe other experimental features?)

[DyXel]

I know the initial PR (#1149) said "advanced / experimental options are not supported", but I was wondering if these could be added so we can use them in our code, at our own risk, and off by default of course.

I was looking to make the changes locally myself in order to test, but the meson.build for curl is pretty big and I don't know exactly where the changes would fit.

[benoit-pierre]

Which experimental options exactly (apart from WebSocket)?

[DyXel]

now that you ask, not sure actually. WebSocket could be the only experimental feature right now 🤔

[benoit-pierre]

Can you wait for the next update? (I'll add it as part of #1466).

[DyXel]

Sure, thanks for looking into this 👍🏻