Implement a compat wrapper for the changes to paged results in python-ldap-2.4

Hello Geert,

python-ldap 2.4 introduced a backwards incompatible change to ldap.controls.SimplePagedResultsControl which was causing issues for me when using python-ad.

This commit adds to the compat module Jeroen van Meeuwen's example of a wrapper for the SimplePagedResultsControl and uses the compat class in ad.client and fixed the issue for me.