As the source of last resort try checking if owner and owner_group in
NFSv4 attributes is purely numeric value. If the check passes then
assume that ID is good and add it to the in-core cache - this deals with
servers which return IDs in form 17@myhost.

Ported from 1.5.x:  9563819d197378b1563523fcb237e61e6e8543f8
Original author: Max Matveev <makc@gmx.co.uk>

Return 'false' in last resort.
Matt Benjamin <matt@linuxbox.com>

Signed-off-by: suhrud <supatank@in.ibm.com>
Signed-off-by: Matt Benjamin <matt@linuxbox.com>
The nfs clients use nfs/hostname princiapl for root.
Map all nfs/* kerberos principals to root.

Ported from 1.5.x: 0a6591be2f0e6d8df71ffa1cc19affd6da9c2a91

Signed-off-by: suhrud <supatank@in.ibm.com>
Signed-off-by: Matt Benjamin <matt@linuxbox.com>

There is no pguid.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Removed compiler warning for idmapper_lookup_by_uname()
Use ANON_UID and ANON_GID in principal2uid() instead of hard coded -2

Signed-off-by: suhrud <supatank@in.ibm.com>

Conflicts:
	src/IdMapper/idmapper.c
	src/IdMapper/idmapper_cache.c
	src/include/idmapper.h

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Fixed principal2uid() to do IDMAP lookup in case the map is not  found
in local cache.
Signed-off-by: suhrud <supatank@in.ibm.com>

Conflicts:
	src/IdMapper/idmapper.c

Signed-off-by: Matt Benjamin <matt@linuxbox.com>