Bug 1009294 - http://www.mozilla.org/en-US/lightbeam/ needs several small updates

Corrections to the Lightbeam About page as described in
https://github.com/mozilla/lightbeam/issues/473

Also removes references to the database server which doesn't exist yet.
Merge pull request #2002 from fmarier/minor_changes_lightbeam

Bug 1009294 - http://www.mozilla.org/en-US/lightbeam/ needs several small updates