Renderer: Never use fog when drawing 3D player sprites

The player sprites are disjoint from the rest of the world in that
they use their own coordinate space that allows them to not Z-collide
into world surfaces. This means world fog is not applicable, as the
psprite Z distance has a different meaning than the world Z distance.
Merge branch 'master' of ssh://github.com/skyjake/Doomsday-Engine
Fixed|libshell: Catch exception from failed server discovery init

If something is blocking network access, a Beacon::PortError exception is
thrown during the ServerFinder constructor. Now the exception is caught and
a warning is printed in the log.
Homepage: Updated source package download page
Merge branch 'master' into revise-map-geometry-generation