ixion: switch SOURCE_URI to tar.xz and https. (#3101)
ixion: switch SOURCE_URI to tar.xz and https. (#3101)

Also add quotes here and there to make sure the recipe will still
be OK if/when "haikuporter --nochroot" is implemented.

haikuports/haikuports,nielx/haikuports,Begasus/haikuports,Begasus/haikuports,haikuports/haikuports,Begasus/haikuports,haikuports/haikuports,moochris/haikuports,nielx/haikuports,moochris/haikuports,nielx/haikuports,Begasus/haikuports,haikuports/haikuports,haikuports/haikuports,moochris/haikuports,Begasus/haikuports