wish: align object relative to a path vertex

It would be nice if it were possible to align an object relative to a specific vertex of a path. Right now, if you have a path vertex selected, it's not possible to select an entire other object which is not itself a path, and it's also not possible to access the normal object alignment commands.

Use case: suppose you have a graph in SVG format, and the axis tickmarks are all one path (rather than one path per line), and you need to realign each tickmark's label to the tickmark, because you changed the font or something.

Related to, but not the same as, bug 171287 and bug 168788.