Adds areFunctions, areStrings, areNumbers, areDates and areRegExps to the UnderscoreJS-Object

UnderscoreJS are-Addon

(function (_) {
	_.each("Function String Number Date RegExp".split(" "), function(name) {
		_["are" + name + (name.substr(-1) !== "s" ? "s" : "")] = function () {
			return _.all(_.toArray(arguments), _["is" + name]);
		}
	});
})(_);