dmd: download additional resources before compiling

Closes #29766.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
Allow building librsvg with GTK+3/Quartz (no X11)
Add standard GNOME themes for gtk+3 and for gtk+ (optionally)
gnome-themes-standard: Make gtk+ mandatory and gtk+3 recommended
gnome-themes-standard: add 3.12.0 bottle.
librsvg: add 2.36.3 bottle.