Improve downloading of OSM data
Improve downloading of OSM data

- use proxy if available
- add support for libsoup-gnome
- check for network errors

Distrotech/libchamplain,potyl/champlain,StanciuMarius/Libchamplain-map-wrapping,potyl/champlain,PabloCastellano/libchamplain,Distrotech/libchamplain,Distrotech/libchamplain,GNOME/perl-Gtk2-Champlain,StanciuMarius/Libchamplain-map-wrapping,Distrotech/libchamplain,PabloCastellano/libchamplain,GNOME/perl-Gtk2-Champlain,StanciuMarius/Libchamplain-map-wrapping,GNOME/perl-Champlain,potyl/champlain,potyl/champlain,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,Distrotech/libchamplain,GNOME/libchamplain,GNOME/perl-Champlain,StanciuMarius/Libchamplain-map-wrapping,PabloCastellano/libchamplain,PabloCastellano/libchamplain,GNOME/libchamplain