Simplifies and streamlines the models used between IMember and IUser along with the services used for both of these entities.

Updates the model used to store and retreive permissions, instead of a single string it is an Enumerable<string> which gives us some flexibility in the future and since this was not public (yet) it's the perfect time to do this.
Removes the base Profile classes from User since these are not required, since we cannot share base classes between Member and User, these weren't necessary.

src/Umbraco.Core/Services/IUserService.cs

@@ -14,9 +14,10 @@ namespace Umbraco.Core.Services
         /// <param name="id">Id of the User to retrieve</param>
         /// <returns><see cref="IProfile"/></returns>
         IProfile GetProfileById(int id);
-
         IProfile GetProfileByUserName(string username);
-        IUser GetUserByUserName(string username);
+
+        //IUser GetUserByUserName(string username);
+
         IUser GetUserById(int id);
 
         /// <summary>