VMOD unix doc fixes.

lib/libvmod_unix/vmod.vcc

@@ -19,6 +19,8 @@ it.
 
 Examples::
 
+  import unix;
+
   sub vcl_recv {
 	# Return "403 Forbidden" if the connected peer is
 	# not running as the user "trusteduser".
@@ -92,7 +94,7 @@ All functions in this VMOD are subject to the following constraints:
 * If the current listener is not a Unix domain socket, or if the
   attempt to read credentials fails, then a ``VCL_Error`` message is
   written to the log. The STRING functions (``vmod_user`` and
-  ``vmod_group``) return NULL, while the INT functions (``vmod_user``
+  ``vmod_group``) return NULL, while the INT functions (``vmod_uid``
   and ``vmod_gid``) return -1.
 
 SEE ALSO