FUSE_DEBUG annotation to show fusion details about a type

[harendra-kumar]

Fusion plugin has a verbose reporting option which prints detailed messages about the fusion process to help in debugging. However, it prints too many messages. Usually, we are working on one particular problem and want to see information only about specific types. We can use a FUSE_DEBUG annotation to do that. If the type has a FUSE_DEBUG on it then we will print verbose information for that type.