Allow additionnal parameters to Directories.get()

By default, a Directories.get() call will retrieve 50 entries. And this is not customizable from the Python client.

An improvement would be to allow to pass any additionnal parameters to that method, such as:

entries = nuxeo.directories.get("nature", pageSize=10, currentPageIndex=1).entries

Doing that will alow to pass even invalid parameters, but we have no way to check them.

Rejected Idea

Another kind of call would be possible:

nuxeo.directories.get("nature", params={"pageSize": 10, "currentPageIndex": 1}).entries

But is is too verbose IMO.