Fix minibar when name or icon are missing; fix source URL in some places; sort dependencies in Makefile

+ Added support for a "?json" query string to return basic data about
  the portal, including its name, sites, banner, URL, and URL root, in
  JSON format.
* Fixed missing support for Firefox Mobile, Chrome on Android, and
  Android tablets not running Honeycomb to is_mobile(), updated its
  documentation, and other changes.  (If, for whatever reason, you're
  using the device type detection in is_mobile(), note that some device
  type names have changed.)
* Fixed missing support for absolute and external icon URLs.
* Now replacing newlines with 
 in site descriptions in HTML
  output (including in title text in minibar mode).  This will fix
  issues with preformatted text.
* Automatic detection of the portal's root directory (where $CONFIG_DIR
  is located).
* This root directory is available in config files as $url_root, and can
  be overridden using the url-root key.
* The purpose of the url key in settings.yaml is now to express the
  owner's *preferred* URL for the portal (e.g. to remove index.php from
  the URL).
* $CONFIG_DIR should not be an absolute path as it is used both in URLs
  and filesystem paths, so the appropriate documentation in the code has
  been changed to reflect that.
* Changed the repository's domain name.

Add support for proxy headers indicating use of SSL, e.g. X-Forwarded-SSL, X-Forwarded-Proto, Front-End-HTTPS

Added the ability to use Templum in site names and descriptions; added warning in settings file about Templum and YAML special chars conflicts