Fixes and documents the odd async usage for reading multipart in a model binder, fixes up navigation.service checks and adds unit tests for that

src/Umbraco.Web.UI.Client/test/unit/common/services/navigation-service.spec.js

@@ -0,0 +1,50 @@
+describe('navigation services tests', function () {
+    var navigationService;
+
+    beforeEach(module('umbraco.services'));
+    beforeEach(module('ngRoute'));
+
+    beforeEach(inject(function ($injector) {
+        navigationService = $injector.get('navigationService');
+    }));
+
+    describe('determine if route change causes navigation', function () {
+
+        it('navigates when parameters added', function () {
+            var currParams = { section: "content", id: 123 };
+            var nextParams = { section: "content", id: 123, create: true };
+            var result = navigationService.isRouteChangingNavigation(currParams, nextParams);
+            expect(result).toBe(true);
+        });
+
+        it('navigates when parameters removed', function () {
+            var currParams = { section: "content", id: 123, create: true };
+            var nextParams = { section: "content", id: 123 };
+            var result = navigationService.isRouteChangingNavigation(currParams, nextParams);
+            expect(result).toBe(true);
+        });
+
+        it('does not navigate when non routing parameters added', function () {
+            var currParams = { section: "content", id: 123 };
+            var nextParams = { section: "content", id: 123, mculture: "abc", cculture: "xyz" };
+            var result = navigationService.isRouteChangingNavigation(currParams, nextParams);
+            expect(result).toBe(false);
+        });
+
+        it('does not navigate when non routing parameters changed', function () {
+            var currParams = { section: "content", id: 123, mculture: "abc" };
+            var nextParams = { section: "content", id: 123, mculture: "ooo", cculture: "xyz" };
+            var result = navigationService.isRouteChangingNavigation(currParams, nextParams);
+            expect(result).toBe(false);
+        });
+
+        it('does not navigate when non routing parameters removed', function () {
+            var currParams = { section: "content", id: 123, mculture: "abc", cculture: "xyz" };
+            var nextParams = { section: "content", id: 123, cculture: "xyz" };
+            var result = navigationService.isRouteChangingNavigation(currParams, nextParams);
+            expect(result).toBe(false);
+        });
+
+    });
+    
+});