Enable usage of an event library like libevent, which might improve performance with big socket sets.
+> ***NOTE:***
+> This method has been deprecated in 2.3.0, please use http\Client::configure() instead.
+
## Params:
* Optional bool $enable = true
* http\Client, self.
+## Throws:
+
+* http\Exception\InvalidArgumentException
+* http\Exception\UnexpectedValueException