Update screen shots

Change-Id: I09e3b3cd496c338ce390c3a82bd7468b7be0b97f
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@nokia.com>

Change-Id: Ia054de58fd1ae6204c327c2a17001a5050128732
Reviewed-on: http://codereview.qt.nokia.com/3405


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Marco Bubke <marco.bubke@nokia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@nokia.com>

Updated qdoc to remove hard-coded dependencies on style sheets.
Simplified the offline documentation, introducing an offline.css
file to be used for documentation in Qt Creator.