[PATCH] clean up release notes - pass 3

Hi,

the attached patch fixes some remaining XHTML validation issues in the release notes.

This is expected to be the last patch for this run. The remaining errors
seem to be related to the use of HTML5-specific features (error, since
the DOCTYPE points to XHTML 1.1) and warnings in some files since they
also contain a BOM (which is said to be potentially problematic with
some rather old browsers).
I'm not planning to touch any of these atm.

[[[
Some more tweaks to make the release XHTML 1.1 standard compliant.

* docs/release-notes/1.7.html
  (atomic-revprops): properly encode & in href

* docs/release-notes/1.8.html
  (auto-reintegrate): close p-tag before ul
  (fsfs-stats): same
  (svnlook-diff): same
  (svn-diff): same
  (issues): rename section id so it doesn't start with a number
]]]

Regards,
Stefan