Revision 1734997

PIVOT-976: More Javadoc fixes for the warnings from Java 8.

Continuing on down the list, basically.  Almost all of these are
@param descriptions, although some are @return and some are @throws.

Also continued a little bit using the Utils.checkNull method in some
places in the components that were updated.  This is a bit off-track
for Javadoc, but there is no separate JIRA for these changes, so ....