Improve PaginatedList docs (#654)

* Improve `PaginatedList` docstring

Include details for each parameter used in PaginatedList.

* Improve `PaginatedList` docstring

Include details for each parameter used in PaginatedList.

* Remove class docstring addition

---------

Co-authored-by: Matthew Emond <me@ucf.edu>

canvasapi/paginated_list.py

@@ -28,6 +28,24 @@ def __init__(
         _url_override=None,
         **kwargs
     ):
+        """
+        :param content_class: The expected type to return in the list.
+        :type content_class: class
+        :param requester: The requester to pass HTTP requests through.
+        :type requester: :class:`canvasapi.requester.Requester`
+        :param request_method: HTTP request method
+        :type request_method: str
+        :param first_url: Canvas endpoint for the initial request
+        :type first_url: str
+        :param extra_attribs: Extra data to include in the request
+        :type extra_attribs: dict
+        :param _root: Specify a nested property from Canvas to use for the resulting list.
+        :type _root: str
+        :param _url_override: "new_quizzes" or "graphql" for specific Canvas endpoints.
+        Other URLs may be specified for third-party requests.
+        :type _url_override: str
+        :rtype: :class:`canvasapi.paginated_list.PaginatedList` of type content_class
+        """
         self._elements = list()
 
         self._requester = requester