fix :enum warnings

Author: joshtynjala

src/feathers/validators/CreditCardValidatorCardType.hx

@@ -25,7 +25,7 @@ package feathers.validators;
 
 	@see `feathers.validators.CreditCardValidator`
 **/
-@:enum abstract CreditCardValidatorCardType(String) from String to String {
+#if haxe4 enum #else @:enum #end abstract CreditCardValidatorCardType(String) from String to String {
 	//--------------------------------------------------------------------------
 	//
 	//  Class constants

src/feathers/validators/CurrencyValidatorAlignSymbol.hx

@@ -25,7 +25,7 @@ package feathers.validators;
 
 	@see `feathers.validators.CurrencyValidator`
 **/
-@:enum abstract CurrencyValidatorAlignSymbol(String) from String to String {
+#if haxe4 enum #else @:enum #end abstract CurrencyValidatorAlignSymbol(String) from String to String {
 	//--------------------------------------------------------------------------
 	//
 	//  Class constants

src/feathers/validators/NumberValidatorDomainType.hx

@@ -23,7 +23,7 @@ package feathers.validators;
 
 	@see `feathers.validators.NumberValidator`
 **/
-@:enum abstract NumberValidatorDomainType(String) from String to String {
+#if haxe4 enum #else @:enum #end abstract NumberValidatorDomainType(String) from String to String {
 	//--------------------------------------------------------------------------
 	//
 	//  Class constants

src/feathers/validators/ZipCodeValidatorDomainType.hx

@@ -24,7 +24,7 @@ package feathers.validators;
 
 	@see `feathers.validators.ZipCodeValidator`
 **/
-@:enum abstract ZipCodeValidatorDomainType(String) from String to String {
+#if haxe4 enum #else @:enum #end abstract ZipCodeValidatorDomainType(String) from String to String {
 	//--------------------------------------------------------------------------
 	//
 	//  Class constants