[php-langspec][Issue #245] - Add curl OOP-style to PHP 8

You can view the Issue on github:
https://github.com/php/php-langspec/issues/245

Opened By: kamil-tekiela
Issue Description:
I would like to propose adding CUrl classes to PHP 8. Currently we do not have classes apart from `CURLFile` class. I think that native implementation of curl in OOP would be a very good idea. 

I have written PoC of what this class could look like. https://github.com/kamil-tekiela/curl

Native implementation would benefit from:
- Inheritance
- Method chaining
- Error reporting as exceptions
- Cleaner syntax