gswauth: admin user is able to delete a reseller admin user

[pushpesh]

Steps:-

#swauth-add-user -a test admin1 testing -K gswauthkey

#swauth-add-user -r test re_admin testing -K gswauthkey

## swauth-list test -K gswauthkey
+----------+
| Users |
+----------+
| admin1 |
| re_admin |
+----------+

#swauth-delete-user test re_admin -U test:admin -K testing

#swauth-list test -K gswauthkey
+--------+
| Users |
+--------+
| admin1 |
+--------+

[pushpesh (psharma)]

Version Info:

glusterfs-openstack-swift-1.10.0-0.27.fc19.noarch

[Thiago da Silva (thiagodasilva)]

fix posted for review in icehouse: http://review.gluster.org/#/c/6516/