Description of problem: fails when adding Ansible Tower with following error: "Endpoints.url has already been taken"


Version-Release number of selected component (if applicable): 5.7.0.10-beta3.20161109111947_9a61b18


How reproducible: always


Steps to Reproduce:
1. go to Configuration> management
2. add a new Ansible Provider
3.

Actual results: fails with  "Endpoints.url has already been taken"

I reproduced it on Beta 1 also.. My appliance is fresh and has no other providers
I tried with 5.6.2 and it worked.

Additional info: from evm.log


[----] I, [2016-11-14T16:39:03.899214 #13854:67cc58]  INFO -- : MIQ(ManageIQ::Providers::AnsibleTower::Provider#with_provider_connection) Connecting through ManageIQ::Providers::AnsibleTower::Prov
ider: [Ansible]
[----] I, [2016-11-14T16:39:07.829680 #13786:5d113c]  INFO -- : MIQ(MiqScheduleWorker::Runner#do_work) Number of scheduled items to be processed: 1.
[----] I, [2016-11-14T16:39:07.835028 #13786:5d113c]  INFO -- : MIQ(MiqQueue.put) Message id: [1000000000063],  id: [], Zone: [default], Role: [smartstate], Server: [], Ident: [generic], Target id
: [], Instance id: [], Task id: [job_dispatcher], Command: [JobProxyDispatcher.dispatch], Timeout: [600], Priority: [20], State: [ready], Deliver On: [], Data: [], Args: []
[----] E, [2016-11-14T16:39:07.991123 #13854:67d0cc] ERROR -- : MIQ(provider_foreman_controller-edit): Endpoints.url has already been taken