Replace calls to `Path.absolute()` and `Path.resolve()` with
`bpathlib.make_absolute(path)`.
The replaced functions can transform drive letters on Windows to UNC
notation. Either all of Flamenco + BAT should be using UNC notation, or
drive letters, but mixing those will cause errors.
The 'None' project finder is the old behaviour of the add-on, and it is not
really necessary. If any of the other finders cannot find the directory
they're looking for, they'll return the current blend file's directory
anyway.
The new default is 'blender project'.
The Flamenco add-on can now find the top-level directory of your Blender
project. It can be configured to find any of these directories:
- `.blender_project`
- `.git`
- `.subversion`
- None, which is the default and the old behaviour of just using the
directory of the current blend file as the 'project directory'.
