Puppet Support

Steps to reproduce bug:

1. Create puppet repository repo1 with feed containing pulp manifest (auto_publish=True)

2. Sync repo1

3. Create puppet repository repo2 with feed containing pulp manifest (auto_publish=True)

4. Sync repo2
repo1 now contains 2 units as expected, while repo2 is empty. This happens only on development version of pulp, not in 2.7 or 2.6.

   $ pulp-admin puppet repo create --repo-id=repo1 --feed=https://repos.fedorapeople.org/pulp/pulp/demo_repos/puppet_manifest/modules/
   Successfully created repository [repo1]
   
   [root@ec2-54-216-139-81 ~]# pulp-admin puppet repo sync run --repo-id repo1
   +----------------------------------------------------------------------+
                       Synchronizing Repository [repo1]
   +----------------------------------------------------------------------+
   
   This command may be exited via ctrl+c without affecting the request.
   
   Downloading metadata...
   [==================================================] 100%
   Metadata Query: 1/1 items
   ... completed
   
   Downloading new modules...
   [==================================================] 100%
   Module: 2/2 items
   ... completed
   
   Task Succeeded
   
   Publishing modules...
   [==================================================] 100%
   Module: 2/2 items
   ... completed
   
   Generating repository metadata...
   [-]
   ... completed
   
   Publishing repository over HTTP...
   ... completed
   
   Publishing repository over HTTPS...
   ... skipped
   
   Task Succeeded
   
   $ pulp-admin puppet repo list
   +----------------------------------------------------------------------+
                             Puppet Repositories
   +----------------------------------------------------------------------+
   
   Id:                  repo1
   Display Name:        None
   Description:         None
   Content Unit Counts:
     Puppet Module: 2
   
   $ pulp-admin puppet repo create --repo-id=repo2 --feed=https://repos.fedorapeople.org/pulp/p
   ulp/demo_repos/puppet_manifest/modules/
   Successfully created repository [repo2]
   
   $ pulp-admin puppet repo sync run --repo-id repo2
   +----------------------------------------------------------------------+
                       Synchronizing Repository [repo2]
   +----------------------------------------------------------------------+
   
   This command may be exited via ctrl+c without affecting the request.
   
   Downloading metadata...
   [==================================================] 100%
   Metadata Query: 1/1 items
   ... completed
   
   Downloading new modules...
   [==================================================] 100%
   Module: 0/0 items
   ... completed
   
   Task Succeeded
   
   Publishing modules...
   [==================================================] 100%
   Module: 0/0 items
   ... completed
   
   Generating repository metadata...
   [-]
   ... completed
   
   Publishing repository over HTTP...
   ... completed
   
   Publishing repository over HTTPS...
   ... skipped
   
   Task Succeeded
   
   $ pulp-admin puppet repo list
   +----------------------------------------------------------------------+
                             Puppet Repositories
   +----------------------------------------------------------------------+
   
   Id:                  repo1
   Display Name:        None
   Description:         None
   Content Unit Counts:
     Puppet Module: 2
   
   Id:                  repo2
   Display Name:        None
   Description:         None
   Content Unit Counts:
   
   $