Request: object snaps to lines

[Kurt Newman <kurt lamer org>]

Right now you can snap objects to grids or lines to objects, but not the
other way around.  Would like to be able to move an object by a snap
point and it automatically connect to the end of a line.

I would find it useful since object sizes dynamically change when the
text amount/size increases.  When this happens, they may no longer
reside on grid lines, thus making it difficult to align the newly
created objects with the rest of your diagram.