Fix intermittent errors due to time zone issues
Fix intermittent errors due to time zone issues

irb(main):001:0> Time.parse('2012-04-06 14:53:54')
=> 2012-04-06 14:53:54 +0100

which does not equal 20120406T145354Z

Use Time.zone.parse and an explicit time zone to avoid this.

lutgendorff/smart-answers,tadast/smart-answers,askl56/smart-answers,alphagov/smart-answers,stwalsh/smart-answers,alphagov/smart-answers,aledelcueto/smart-answers,stwalsh/smart-answers,askl56/smart-answers,lutgendorff/smart-answers,aledelcueto/smart-answers,tadast/smart-answers,lutgendorff/smart-answers,ministryofjustice/smart-answers,alphagov/smart-answers,aledelcueto/smart-answers,tadast/smart-answers,askl56/smart-answers,lutgendorff/smart-answers,tadast/smart-answers,askl56/smart-answers,ministryofjustice/smart-answers,aledelcueto/smart-answers,stwalsh/smart-answers,ministryofjustice/smart-answers,alphagov/smart-answers,stwalsh/smart-answers