@Builder isn't useful for java interop

See https://github.com/groovy/groovy-eclipse/issues/178 for context. The javadoc for the @Builder AST annotation indicate that it might be good for Java interoperability, however it appears that this is not the case. This should be removed from the javadoc for this annotation.

Specifically it says "But if you need Java integration or in some cases improved type safety, the @Builder transform might prove very useful."