Shady nagy/blazor enhance (#429)

* - Using cdnjs not nuget on bootstrap and signalr.
- Bootstrap modal used for add, edit details and delete.

* EditForm inside modal-content

* Top close button action added

* Removed unused using.

* DeleteCookies moved inside AuthService

* ApplicationCore removed from BlazorAdmin dependencies

* SecureHttpClient removed

* Logout from identity manager added

* last thing to do in logout from admin is LogoutIdentityManager.

* JSRuntime used in AuthService without pass to the functions

* Link fixed when logout from MVC

src/BlazorAdmin/_Imports.razor

@@ -9,7 +9,6 @@
 @using Microsoft.JSInterop
 @using BlazorAdmin
 @using BlazorAdmin.Shared
-@using BlazorAdmin.Network
 @using BlazorAdmin.Services
 @using BlazorAdmin.Services.CatalogBrandService
 @using BlazorAdmin.Services.CatalogItemService