Remove social widgets when debugging

Social widgets increase load times, add uncontrolled JavaScript code,
and open potential security holes.  None of these are desirable,
especially when debugging.  This commit removes the Twitter and Google
Plus widgets, at least when the window location has a query string
(e.g. "?mode=RAW").
Merge pull request #485 from twpayne/no-social-widgets-when-debugging

Remove social widgets when debugging