[Browser] Use a slash in the user-agent (BGO#606669)
[Browser] Use a slash in the user-agent (BGO#606669)

This is compliant with RFCs 1945 and 2068.

babycaseny/banshee,directhex/banshee-hacks,dufoli/banshee,Carbenium/banshee,Carbenium/banshee,lamalex/Banshee,lamalex/Banshee,stsundermann/banshee,ixfalia/banshee,dufoli/banshee,ixfalia/banshee,stsundermann/banshee,babycaseny/banshee,stsundermann/banshee,ixfalia/banshee,stsundermann/banshee,petejohanson/banshee,GNOME/banshee,GNOME/banshee,arfbtwn/banshee,directhex/banshee-hacks,Dynalon/banshee-osx,allquixotic/banshee-gst-sharp-work,lamalex/Banshee,babycaseny/banshee,ixfalia/banshee,allquixotic/banshee-gst-sharp-work,GNOME/banshee,mono-soc-2011/banshee,GNOME/banshee,petejohanson/banshee,lamalex/Banshee,GNOME/banshee,dufoli/banshee,dufoli/banshee,babycaseny/banshee,babycaseny/banshee,ixfalia/banshee,arfbtwn/banshee,Dynalon/banshee-osx,GNOME/banshee,petejohanson/banshee,Dynalon/banshee-osx,allquixotic/banshee-gst-sharp-work,GNOME/banshee,Dynalon/banshee-osx,Carbenium/banshee,arfbtwn/banshee,stsundermann/banshee,petejohanson/banshee,Carbenium/banshee,Dynalon/banshee-osx,dufoli/banshee,mono-soc-2011/banshee,dufoli/banshee,babycaseny/banshee,allquixotic/banshee-gst-sharp-work,petejohanson/banshee,dufoli/banshee,arfbtwn/banshee,directhex/banshee-hacks,mono-soc-2011/banshee,GNOME/banshee,stsundermann/banshee,Dynalon/banshee-osx,stsundermann/banshee,dufoli/banshee,arfbtwn/banshee,arfbtwn/banshee,Dynalon/banshee-osx,allquixotic/banshee-gst-sharp-work,Dynalon/banshee-osx,directhex/banshee-hacks,petejohanson/banshee,mono-soc-2011/banshee,stsundermann/banshee,babycaseny/banshee,Carbenium/banshee,ixfalia/banshee,arfbtwn/banshee,lamalex/Banshee,ixfalia/banshee,Carbenium/banshee,mono-soc-2011/banshee,babycaseny/banshee,mono-soc-2011/banshee,arfbtwn/banshee,ixfalia/banshee,allquixotic/banshee-gst-sharp-work,lamalex/Banshee,mono-soc-2011/banshee,directhex/banshee-hacks,directhex/banshee-hacks