Adding interface IMultiTenantUserService

The id provider connectors that support MultiTenants will implement this
interface
Implement AuthenticateLocal for MembershipReboot

Adding the multiTenant implementation for membershipReboot for local
authentication
Authenticate locally using the multiTenant implementation

MultiTenant authentification now uses the implementation of
IMultiTenantUserService
Implement external Authentication for MembershipReboot

Now if you login from an external source will login to the user within
the same tenant and if the user doesn't exist will link it to a new user
created inside to the requested tenant
Use the external Authentication from the controller

We are using the Implementation for external authentication from the
AuthenticationController
Adding client example for mutitenant login

Adding multitenant client example for Javascript Implicit Client and
adding the url of the new project on the client.
Adding missing files to the client
Multitenancy support for TestUserService

The password has to be the tenant + "_" + username.
eg:
tenant = myTenant
user = myUser
password = myTenant_myUser
Adding the claim tenant for logged in user

We are adding the claim "tenant" to the identity when the user is logged
in if the application is in multitenant mode.
This will allow us to validate if the identity belongs to the requested
tenant in future accesses
Validate that the user belongs to the requested tenant

We are adding extra logic to validate that the user belongs to the
requested tenant if the application is in multitenant mode
Changing the title of the client example
Use constant instead of string