TESTS: Add wrappers to request a user or a group by ID Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>

intg: Fix python3 issues NamedTemporaryFile use the default mode 'w+b' and we tried to write strings. It is not a problem on python2 but failed on pyhton3 Python module ctypes directly uses C functions from libraries. C functions usually expect/returns "char *" when string is expected. But python3 uses unicode for string. Decoding returned bytes ("char *") to unicode strings simplify tests in python3. Otherwise we would need to convert bytes to string in each assertion. Reviewed-by: Martin Basti <mbasti@redhat.com>

TESTS: Add a module to call nss_sss's getpw* from tests Implements a python module that allows to load the nss_sss module and simulate calling getpw* functions from tests. Reviewed-by: Pavel Březina <pbrezina@redhat.com> Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>