Port to autovox

This converts avox to be based on autovox instead of using its own managing code.

For users, this means you also need to load the autovox xontrib (xontrib load autovox) at startup.

For more information about autovox, see the xonsh docs.

Moving forward, this should provide better interoperability with other policies.

Bug Fix

• Fix deprecation warnings

Events!

Now uses the on_chdir event instead of aliasing cd. So now this works with pushd, popd, z, and anything else that changes the current directory.

0.4

This is primarily a windows-compatibility release, although there are some bugfixes, too.

v0.3

No longer interfere with other cd-related xontribs (namely, autoxsh).