Change to ASF httpd vulnerability XML format

[Mark Cox <mjc () apache org>]

Various OSS projects I've been involved with use a master vulnerability
database in XML used for various internal functions such as generating web
pages.  I know some folks monitor or use/convert these XML feeds too even
though we've not really publicised them or given them a schema.

Later today I will be performing a major update to the Apache HTTP Server
XML file[1] so that each CVE has a unique entry (rather than currently
where the issues are repeated for each major version affected).  This
brings it more into line with the OpenSSL XML file[2] and allows us to
automate more of our release process (i.e. generating the required JSON for
Mitre CVE submissions).

Some entries will have other minor updates to their text and to fix link
locations so if you are monitoring the html pages you will see some minor
changes at that time.

Regards, Mark J Cox

[1] https://httpd.apache.org/security/vulnerabilities-httpd.xml
[2] https://www.openssl.org/news/vulnerabilities.xml