Install icon and .desktop file during make install

Makes packagers' lives easier, looks better and ensures Julia
will show up in software centers like GNOME Software.

Makefile

@@ -256,6 +256,13 @@ endif
  -rm -f $(DESTDIR)$(datarootdir)/julia/doc/juliadoc/.gitignore
  # Copy in beautiful new man page!
  $(INSTALL_F) $(build_datarootdir)/man/man1/julia.1 $(DESTDIR)$(datarootdir)/man/man1/
+ # Copy icon and .desktop file
+ mkdir -p $(DESTDIR)$(datarootdir)/icons/hicolor/scalable/apps/
+ $(INSTALL_F) contrib/julia.svg $(DESTDIR)$(datarootdir)/icons/hicolor/scalable/apps/
+ -touch --no-create $(DESTDIR)$(datarootdir)/icons/hicolor/
+ -gtk-update-icon-cache $(DESTDIR)$(datarootdir)/icons/hicolor/
+ mkdir -p $(DESTDIR)$(datarootdir)/applications/
+ $(INSTALL_F) contrib/julia.desktop $(DESTDIR)$(datarootdir)/applications/
 
  # Update RPATH entries of Julia if $(private_libdir_rel) != $(build_private_libdir_rel)
 ifneq ($(private_libdir_rel),$(build_private_libdir_rel))

contrib/julia.desktop

@@ -0,0 +1,8 @@
+[Desktop Entry]
+Name=Julia
+Comment=High-level, high-performance dynamic language for technical computing
+Exec=julia
+Icon=julia
+Terminal=true
+Type=Application
+Categories=Development;ComputerScience;Building;Science;Math;NumericalAnalysis;ParallelComputing;DataVisualization;ConsoleOnly;