Add information on common inter-recipe dependencies

From qschulz (via Matrix):

wondering if we could also add information on common inter-recipe dependencies (e.g. DEPENDS is do_configure[depends] += "recipeB:do_populate_sysroot" (or is it do_prepare_recipe_sysroot? I always mix both)) so something like a text above the "dependency arrow" between what you call clusters, to explicit if it's DEPENDS or RDEPENDS/RRECOMMENDS