A DESCRIPTION OF THE PROBLEM :
The "-packagesheader" option for javadoc was apparently added a long time ago, but it's never been documented. I found http://bugs.java.com/bugdatabase/view_bug.do?bug_id=4770521 . I would add an additional comment to that, but I don't have that ability.
Because of the lack of this documentation, other tools that interface with javadoc have not implemented an interface for this option, so the problem is cascading.
URL OF FAULTY DOCUMENTATION :
http://docs.oracle.com/javase/8/docs/technotes/tools/windows/javadoc.html#options