The ASP.NET Universal Providers contained in System.Web.Providers are now included with the MVC 4 templates and are being presented as replacements for the Membership and Profile providers that have come with ASP.NET for some time now (SqlMembershipProvider, SqlProfileProvider, SqlRoleProvider). These providers now make use of entity framework (seems like 4.0) for data access and generating their respective tables. The membership entities for example look like this 

```
[EdmEntityType(NamespaceName="System.Web.Providers.Entities", Name="Membership")]
public class MembershipEntity : EntityObject

```

Is there a way to easily extend the included EntityObjects or tweak the generated db schema to create most customized entities i.e. make columns null-able, add/remove columns?