Open issues target pages

All open issues incorrectly point to issue 151#. Refer to the affected text
(and possibly more out there) -

"...There are also a number of open issues related to this document, for
which working-group decisions still need to be made:

•issue 30 (longdesc)

•issue 133 (modal attribute)

•issue 134 (tab states)

•issue 150 (code-point verbosity)

•issue 151 (whatwg references)

•issue 153 (link-external)

•issue 154 (link-sidebar)

•issue 164 (no hgroup)

•issue 165 (rel-pingback)..."

Page url: https://www.w3.org/TR/2011/WD-html5-author-20110809/spec.html

-Devarshi