v1.4.0: Switched to a global exception handler.

This new release brings the following features:

• Switched to using PDO's associative-array fetching mode (FETCH_ASSOC) instead of object fetching mode (FETCH_OBJ)
• The Site class is no longer responsible for rendering the main parts of the site; instead, a dedicated renderer was added
• Switched to a global exception handler. This removes the need for each page to handle its exceptions

Released version 1.3.7

• Some improvements to exception handling
• Upgraded jQuery UI: 1.10.4 -> 1.11.0