Moved fake manager creation and initial configuration into the proxy generator (Part I)

This is the first part of PR #372 (we split it up into 2 PRs as mentioned there).

It solves #371 partially, namely that the default behavior is available inside the c'tor call. Therefore it also solves the bug #368 (see the `when_faking_a_class_which_calls_virtual_property_members_in_constructor` test case).
Sorry, I'm not quite following this comment.
(A minor thing, but I think "before initializing the first call of Fetch or EnsureInitialized" perhaps should be "before the first call to Fetch or EnsureInitialized", but maybe not, as I still don't follow.)

The claim is that we only need to be able to serialize a FakeManagerProvider after Fetch or EnsureIntialized is called? If we're trying to serialize it beforehand, we'll lose the `fakeManagerFactory` and `fakeManagerAccessor` and `configurer`, no?

Ah. It's because until either of `Fetch` and `EnsureInitialized` is called, there's no containing `ProxyInterceptor` or `DelegateCallInterceptedEventRaiser` that will be cloned. Yes?