Eager vs. lazy coercion in BeanAdapter

[gk-brown]

I just added this to the README, but thought it might be worth mentioning here as well. When using the coerce() method of BeanAdapter, there are a few distinctions between converting to an interface versus a concrete type (i.e. a class or record). Obviously, an interface is simpler to declare and thus easier to maintain. On the other hand, since it is implemented by a dynamic proxy and backed by a map, it will most likely be slightly less efficient.

However, an important functional distinction is that concrete types are coerced "eagerly" (before coerce() returns), while interfaces are coerced "lazily" (when a property is accessed). Depending on use case, this may make one option or the other more compelling or applicable.