use sfa.client.client_helper to generate users list in CreateSliver

diff --cc sfa/client/sfi.py
index 838b291,838b291..384d6f1
--- 1/sfa/client/sfi.py
--- 2/sfa/client/sfi.py
+++ b/sfa/client/sfi.py
@@@ -16,7 -16,7 +16,7 @@@ from lxml import etre
  from StringIO import StringIO
  from types import StringTypes, ListType
  from optparse import OptionParser
--
++from sfa.client.client_helper import pg_users_arg, sfa_users_arg, sfa_to_pg_users_arg 
  from sfa.util.sfalogging import sfi_logger
  from sfa.trust.certificate import Keypair, Certificate
  from sfa.trust.gid import GID
@@@ -980,37 -980,37 +980,17 @@@ class Sfi
          #    keys: [<ssh key A>, <ssh key B>] 
          #  }]
          users = []
--        all_keys = []
--        all_key_ids = []
          slice_records = self.registry.Resolve(slice_urn, [user_cred.save_to_string(save_parents=True)])
          if slice_records and 'researcher' in slice_records[0] and slice_records[0]['researcher']!=[]:
              slice_record = slice_records[0]
              user_hrns = slice_record['researcher']
              user_urns = [hrn_to_urn(hrn, 'user') for hrn in user_hrns]
              user_records = self.registry.Resolve(user_urns, [user_cred.save_to_string(save_parents=True)])
--            for user_record in user_records:
--                if user_record['type'] != 'user':
--                    continue
--                #user = {'urn': user_cred.get_gid_caller().get_urn(),'keys': []}
--                user = {'urn': user_cred.get_gid_caller().get_urn(), #
--                        'keys': user_record['keys'],
--                        'email': user_record['email'], #  needed for MyPLC
--                        'person_id': user_record['person_id'], # needed for MyPLC
--                        'first_name': user_record['first_name'], # needed for MyPLC
--                        'last_name': user_record['last_name'], # needed for MyPLC
--                        'slice_record': slice_record, # needed for legacy refresh peer
--                        'key_ids': user_record['key_ids'] # needed for legacy refresh peer
--                } 
--                users.append(user)
--                all_keys.extend(user_record['keys'])
--                all_key_ids.extend(user_record['key_ids'])
--            # ProtoGeni Aggregates will only install the keys of the user that is issuing the
--            # request. So we will add all to the current caller's list of keys
++            
              if 'sfa' not in server_version:
--                for user in users:
--                    if user['urn'] == user_cred.get_gid_caller().get_urn():
--                        user['keys'] = all_keys  
--
++                users = pg_users_arg(user_records)
++            else:
++                users = sfa_users_arg(user_records, slice_record)
          call_args = [slice_urn, creds, rspec, users]
          if self.server_supports_call_id_arg(server):
              call_args.append(unique_call_id())

diff --cc sfa/managers/slice_manager_pl.py
Simple merge