Remove non-essential platform services
Remove non-essential platform services

- Remove services that can be registered by the application itself.
- These services use to come from the DNX but now they are stand alone
implementations that can be registered by applications if they choose.

#501

aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore