Add rewrite rules, improve install doc

- Added rewrite rule to etc/httpd/global.conf so the about
  history page is now served from Bedrock
- Added permanent redirect rules so any requests for the old about
  bookmarks.html or timeline.html pages will be redirected to the
  corresponding new pages on the wiki
- Added some more information to the install doc about getting the PHP
  and Bedrock sides of the site running locally with Apache.

Bug 849426