On double click, center to the clicked area
On double click, center to the clicked area

Makes us behave the same way as google maps.

Signed-off-by: Jiří Techet <af18a4329e30c3b95edc4d3e647176d16d87c9c7@gmail.com>

StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,Distrotech/libchamplain,PabloCastellano/libchamplain,Distrotech/libchamplain,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain,GNOME/libchamplain,Distrotech/libchamplain,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,Distrotech/libchamplain,GNOME/libchamplain