Added a double button press handler - when the button is pressed twice, it emulates button 3. This allows touch screens to zoom out.
Added a double button press handler - when the button is pressed twice, it emulates button 3.
This allows touch screens to zoom out.

drahnr/gtkdatabox-radioactive,drahnr/gtkdatabox-radioactive,drahnr/gtkdatabox-radioactive,drahnr/gtkdatabox-radioactive