connection with timeout option

About this https://github.com/nrk/phpiredis/issues/31

New option when you create a phpredis_connect
phpiredis_connect($ip [, int $port, int $timeout ] );
$timeout is optionnal and is in millisecond
It's work with phpiredis_pconnect too.

example:
phpiredis_connect('127.0.0.1' , 6379, 20 );