[ADF-1694] Datepicker should be localizable (#2471)

* Add locate as user preference property

* The datepicker should be localizable.
Save the locale as user preference
The app should get the default locale from the store or appcongif or Browser or en

* Fix build error

* Fix unit test date widget

* Needs more investigation

* Fix import UserPreference

* Rollback date format change

demo-shell-ng2/app/components/app-layout/app-layout.component.html

@@ -37,7 +37,7 @@
         <mat-menu #langMenu="matMenu">
             <button mat-menu-item (click)="changeLanguage('en')">English</button>
             <button mat-menu-item (click)="changeLanguage('it')">Italian</button>
-            <button mat-menu-item (click)="changeLanguage('ru')">Russian</button>
+            <button mat-menu-item (click)="changeLanguage('ja-JP')">Japanese</button>
         </mat-menu>
 
         <button mat-icon-button (click)="sidenav.open()">