Make php-curl required

I think composer should alert you, when you're installing this package and don't have php-curl extension installed, cause if you don't, that causes weird behaviour while creating Sabre\HTTP\Client.

Curl is only required when using the Client class. All other classes dont require it.

Therefore we only declare it a suggested dependency

http/composer.json

Line 19 in af4612a

"ext-curl" : " to make http requests with the Client class"

What kind of weird behavior do you mean exactly?

Sorry for the late answer - weird behaviour in my case is, some kind of error throwing on asking curl constant (CURLOPT_RETURNTRANSFER if I remember correctly), but not catchable and that is not causing fatal error and request is continuing execution from some other place. Maybe that's something in the Laravel, but that's it - on meeting the line with curl constant, it just going up skipping some levels of call stack and going further.

I guess you're right about suggested dependency and library user of Client class should require ext-curl indeed.