Make gitto.el work with the latest gitto
Make sure to deal with a repository

When checking when a repository is known or not be sure that there is
actually a chance that we are looking at a repository. If the thing to
be checked is neither a `<repository>' instance nor a string it's sure
that it's also not a registered repository.
Allow directory specification for config update

Add an optional directory parameter to the `config update' and `config
hooks' commands, which, if specified, will limit any updates to the
given repository.
Makefile: Put path and main in order of dependence

The `main' module depends on `path', not the other way around, just to
be sure to keep away compilation warnings or double compilation compile
`path' first.