paged results: tests without server_sort ctrl

paged results: tests without server_sort ctrl

On windows, adding or modifying a record during a paged results search
behaves differently depending on whether or not you supply server_sort
control.  This patch adds tests and documentation.

Signed-off-by: Aaron Haslett <aaronhaslett@catalyst.net.nz>
Reviewed-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
Autobuild-Date(master): Fri Aug 30 08:26:21 UTC 2019 on sn-devel-184