Fixed #9077: Modified the database installation notes to point to somewhere...

Fixed #9077: Modified the database installation notes to point to somewhere useful, rather than initd.org's rant page about Trac. Thanks to velo for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@9025 bcc190cf-cafb-0310-a4f2-bffc1f526a37