Executes $apply() only if doesn't have another in execution (blur)

Some components, like datepickers or combo boxes or autocompletes,
has $apply() in her codes to "apply" something. Like this, sometimes
"angular-validation" needs apply something too.

When "angular-validation" applies something to some component and
that component executes $apply() before the validation, an error is
displayed in console: "$apply already in progress".

To correct this, just verify if $apply() is in progress.
If it isn't in progress execute him. If it is in progress,
doesn't execute him.

dist/angular-validation.js

@@ -796,9 +796,14 @@ angular.module('validation.directive', ['validation.provider']);
         if (validMethod === 'blur') {
           element.bind('blur', function() {
             var value = scope.$eval(ngModel);
-            scope.$apply(function() {
+
+            if (scope.$root.$$phase !== '$apply') {
+              scope.$apply(function() {
+                checkValidation(scope, element, attrs, ctrl, validation, value);
+              });
+            } else {
               checkValidation(scope, element, attrs, ctrl, validation, value);
-            });
+            }
           });
 
           return;

src/validator.directive.js

@@ -418,9 +418,14 @@
         if (validMethod === 'blur') {
           element.bind('blur', function() {
             var value = scope.$eval(ngModel);
-            scope.$apply(function() {
+
+            if (scope.$root.$$phase !== '$apply') {
+              scope.$apply(function() {
+                checkValidation(scope, element, attrs, ctrl, validation, value);
+              });
+            } else {
               checkValidation(scope, element, attrs, ctrl, validation, value);
-            });
+            }
           });
 
           return;