Created by: jonathonf
This refactors out the duplicated desktop launchers, replacing them with a template which is used by the Makefile to generate a launcher for each application.
It also fixes the default icon installation location to remove the implicit dependency on hicolor-icon-theme and place them in the default icon search path.
Packagers could use e.g. imagemagick to rescale the 1024x1024 icon and install smaller icons into the appropriate hicolor icon locations.