Add built in support for Autofac lifecycles

[daniellittledev]

When using MicroBus.Autofac dependencies that are registered with InstancePerLifetimeScope() should be scoped to a message passing through the bus.

See http://docs.autofac.org/en/latest/faq/per-request-scope.html

[daniellittledev]

This should be handled in the layer above invoking the bus.

[daniellittledev]

There may be room to make an interceptor style enhancement to make this easier.

[daniellittledev]

Support for scopes has been added, for Autofac BeginLifetimeScope is used for each call (send, publish, query) on the bus.