Handle some basic cases of `INVOKEDYNAMIC` in call graph construction

[johannesduesing]

As discussed in #229, we might want to handle some cases of INVOKEDYNAMIC in CG construction when we load class files without rewriting them. In that specific instance, a call to a lambda-instance of Runnable was not found because it was instantiated via a dynamic invocation.

Find out how this would be possible, and what kinds of cases we may want to handle.