inotify: fix
issue1375, add a test.
The biggest problem was the data structure, which did not allow changing
a file into a directory or vice versa. This problem is fixed by
b55d44719b47.
The walk() method also had an issue in this case:
- we know 'path' as a directory. inotify server sleeps.
- 'path' is deleted
- 'path' is recreated as a file
- the server catches up here, and see the deletion. it instantiates a scan(),
which in its turn calls for walk(repo, path).
- walk() then assumes that 'path' is a directory and calls os.listdir on it,
which raises an OSError(errno.ENOTDIR)
Catch the error, and yield the file instead of the directory contents.