Provides interface to libevent library
This is an extension to efficiently schedule I/O, time and signal based
events using the best I/O notification mechanism available for specific platform.
This is a port of libevent to the PHP infrastructure.
Version 1.0.0 introduces:
* new OO API breaking backwards compatibility
* support of libevent 2+ including HTTP, DNS, OpenSSL and the event listener.
Note, event-1.0.0 and greater is not compatible with previous versions.