Handle directory adds.
Handle symlinks in commit.
Handle execute in commit.
Handle auto-props on file adds.
Handle directory deletes.
Test coverage is horrible. Figure out a strategy to have some real tests.
Be more explicit about deletes in diff-replay because then we can probably
handle a rename like ``mv Foo foo '' properly.
Use replay_range on svn 1.5, it will make replay-over-serf faster.
Add convertedrev to extra on hg-side commit.

Known upstream issues:
Using serf as the http library causes no revisions to convert. (svn trunk and 1.5.x branch as of 
r33158 both have this. No idea bout 1.4.x, since I always just use neon there).
This is fixed in Subversion trunk in revision 33173. I don't know if it has been backported to 
the 1.5.x branch yet.