Description of problem: Unable to produce a database backup through the Web UI.  The NFS storage mounts and creates a directory path but no .backup file is created.


Version-Release number of selected component (if applicable): 5.4.5.2


How reproducible: Always


Steps to Reproduce:
1. Initiate a one time database backup through the Web UI via NFS storage.
2.
3.

Actual results: Receive the Error: [No such file or directory - /root/.pgpass].  Directory is created through NFS but no backup database is created. 


Expected results: Expecting a database to be created.


Additional info:

[----] I, [2016-09-09T07:11:33.637748 #6660:108be88]  INFO -- : MIQ(MiqQueue.get_via_drb) Message id: [1000013471352], MiqWorker id: [1000000068504], Zone: [], Role: [database_operations], Server: [], Ident: [generic], Target id: [], Instance id: [], Task id: [], Command: [DatabaseBackup.gc], Timeout: [600], Priority: [100], State: [dequeue], Deliver On: [], Data: [], Args: [{:userid=>"admin", :task_id=>1000000352977}], Dequeued in: [4.852345804] seconds
[----] I, [2016-09-09T07:11:33.637909 #6660:108be88]  INFO -- : MIQ(MiqQueue.deliver)    Message id: [1000013471352], Delivering...
[----] I, [2016-09-09T07:11:33.639524 #6660:108be88]  INFO -- : MIQ(MiqTask.update_status) Task: [1000000352977] [Active] [Ok] [Starting DB GC for Region: region_1]
[----] I, [2016-09-09T07:11:33.644588 #6660:108be88]  INFO -- : MIQ(MiqPostgresAdmin.run_cmd) Running command... vacuumdb --no-password --dbname vmdb_production --username root
[----] E, [2016-09-09T07:11:33.644953 #6660:108be88] ERROR -- : MIQ(MiqQueue.deliver)    Message id: [1000013471352], Error: [No such file or directory - /root/.pgpass]
[----] E, [2016-09-09T07:11:33.645070 #6660:108be88] ERROR -- : [Errno::ENOENT]: No such file or directory - /root/.pgpass  Method:[rescue in deliver]
[----] E, [2016-09-09T07:11:33.645197 #6660:108be88] ERROR -- : /var/www/miq/vmdb/lib/db_administration/miq_postgres_admin.rb:227:in `delete'
[----] I, [2016-09-09T07:11:33.645377 #6660:108be88]  INFO -- : MIQ(MiqQueue.delivered)  Message id: [1000013471352], State: [error], Delivered in [0.007461316] seconds
[----] I, [2016-09-09T07:11:33.646933 #6660:108be88]  INFO -- : MIQ(MiqQueue.m_callback) Message id: [1000013471352], Invoking Callback with args: ["Finished", "error", "No such file or directory - /root/.pgpass", "nil"]
[----] I, [2016-09-09T07:11:33.647337 #6660:108be88]  INFO -- : MIQ(MiqTask.update_status) Task: [1000000352977] [Finished] [Error] [No such file or directory - /root/.pgpass]