Update 4. Add auth features.md (#82)

Author: natemcmaster

docs/4. Add auth features.md

@@ -156,7 +156,7 @@ In this module we're going to add the capability for users to register and sign-
 1. Run the Identity scaffolder again, but this time select the `Account\Register` page in the list of files to override and select the `IdentityDbContext (FrontEnd.Data)`
    * On command line, run
      ```
-     dotnet aspnet-codegenerator identity --files Account.Register
+     dotnet aspnet-codegenerator identity --dbContext FrontEnd.Data.IdentityDbContext --files Account.Register
      ```
 1. Update the `RegisterModel` class in the `Register.cshtml.cs` file to accept `IAdminService` and `IdentityDbContext` parameters and save them to local members:
     ``` c#