sdformat8: depend on urdfdom (#988)
sdformat8: depend on urdfdom (#988)

* sdformat8: depend on urdfdom

* sdformat8: patch to fix build with urdfdom

* sdformat8: update use external urdfdom bottle.

Co-authored-by: OSRF Build Bot <e7ccba6b2e9a009fc519e029a919f6da63312f55@osrfoundation.org>
scpeters/homebrew-simulation,osrf/homebrew-simulation,j-rivero/homebrew-simulation