Nightingale make install

Makefile

    ifeq (, $(filter linux, $(OSTYPE)))
        $(error Installing using make is currently not supported on your operating system)
    endif

	$(CP) $(DISTDIR) /usr/lib/nightingale
	ln -s /usr/lib/nightingale/nightingale /usr/bin/nightingale
	xdg-icon-ressource install --novendor --size 512 $(DISTDIR)/chrome/icons/default/default.xpm nightingale
	xdg-desktop-menu install --novendor $(TOPSRCDIR)/debian/nightingale.desktop