Add ability to put any parameter into query

Add an OO way to put in any LQL parameter. See the following example:

$hosts = $client
	->get("hostsbygroup")
	->column("name")
	->column("state")
	->filter("state != 0")
	->parameter("Filter: hostgroup = foo-hostgroup")
	->parameter("Filter: hostgroup = bar-hostgroup")
	->parameter("Or: 2")
	->execute();

Being able to pass any query to execute() introduced in 35b25ce5 is nice
but being able to keep an OO mindset is even better when possible.