jQuery.validator.addMethod("alphanumeric", function(value, element) {
	return this.optional(element) || /^\w+$/i.test(value);
}, "Letters, numbers, spaces or underscores only please");

jQuery.validator.addMethod("lettersonly", function(value, element) {
	return this.optional(element) || /^[a-z]+$/i.test(value);
}, "Letters only please"); 

jQuery.validator.addMethod("integer", function(value, element) {
	return this.optional(element) || /^-?\d+$/.test(value);
}, "A positive or negative non-decimal number please");

jQuery.validator.addMethod("time", function(value, element) {
		return this.optional(element) || /^([01][0-9])|(2[0123]):([0-5])([0-9])$/.test(value);
	}, "Please enter a valid time, between 00:00 and 23:59"
);