Additionals: fix typo, simplify regex

Closes jquery-validation#1066

Author: jrowens

src/additional/zipcodeUS.js

@@ -1,3 +1,3 @@
 jQuery.validator.addMethod("zipcodeUS", function(value, element) {
-	return this.optional(element) || /^\d{5}-\d{4}$|^\d{5}$/.test(value);
+	return this.optional(element) || /^\d{5}(-\d{4})?$/.test(value);
 }, "The specified US ZIP Code is invalid");

src/additional/ziprange.js

@@ -1,3 +1,3 @@
 jQuery.validator.addMethod("ziprange", function(value, element) {
 	return this.optional(element) || /^90[2-5]\d\{2\}-\d{4}$/.test(value);
-}, "Your ZIP-code must be in the range 902xx-xxxx to 905-xx-xxxx");
+}, "Your ZIP-code must be in the range 902xx-xxxx to 905xx-xxxx");