Pulp

pulp-admin repo list -s fails if a repository does not have a "--display-name" associated.

To reproduce in 2.8.x:

1. pulp-admin repo list -s
   euca2ools-3.3-centos6-x86_64 euca2ools-3.3-centos6-x86_64
   my_own_pypi my_own_pypi
   mongodb-rhel6-x86_64 mongodb-rhel6-x86_64
   mongodb-rhel7-x86_64 mongodb-rhel7-x86_64
   An unexpected error has occurred. More information may be found using the -v
   flag.

1. pulp-admin rpm repo list
   Id: mongodb-rhel7-x86_64
   Display Name: mongodb-rhel7-x86_64
   Description: mongodb-rhel7-x86_64
   Content Unit Counts:
   Rpm: 25

Id: saltstack-rhel7-x86_64
Display Name: None
Description: None
Content Unit Counts:
Rpm: 60
Srpm: 20

1. pulp-admin rpm repo update --display-name saltstack-rhel7-x86_64 --repo-id saltstack-rhel7-x86_64
   Repository [saltstack-rhel7-x86_64] successfully updated
2. pulp-admin rpm repo update --display-name saltstack-rhel6-x86_64 --repo-id saltstack-rhel6-x86_64
   Repository [saltstack-rhel6-x86_64] successfully updated

1. pulp-admin repo list -s
   euca2ools-3.3-centos6-x86_64 euca2ools-3.3-centos6-x86_64
   my_own_pypi my_own_pypi
   mongodb-rhel6-x86_64 mongodb-rhel6-x86_64
   mongodb-rhel7-x86_64 mongodb-rhel7-x86_64
   saltstack-rhel7-x86_64 saltstack-rhel7-x86_64
   saltstack-rhel6-x86_64 saltstack-rhel6-x86_64