Change all "software.llnl.gov" and "software.ornl.gov" absolute links on HTML/MarkDown pages to be relative links

There are several links which are coded to point to the specific domain software.llnl.gov or software.ornl.gov . We want to change the href of these properties to not directly include the domain in them.

While using relative paths from the site root (i.e. /news/) will generally be the best approach, it's okay to sometimes use paths not from the root (i.e. news/page.html), as long as the link is included in page-specific content. (So the navbar links will require paths from the site root, for example.)

LLNL -> ORNL

Change www.llnl.gov to www.ornl.gov, or https://llnl.gov to https://ornl.gov if present.