[zanata/zanata-platform] f2e4e5: use xvfb-run instead of Xvfb plugin

[GitHub]

  Branch: refs/heads/Jenkinsfile
  Home:   https://github.com/zanata/zanata-platform
  Commit: f2e4e5d7303de97268b3f6b6ca27c133773a8526
      https://github.com/zanata/zanata-platform/commit/f2e4e5d7303de97268b3f6b6ca27c133773a8526
  Author: Ding-Yi Chen <dchen at redhat.com>
  Date:   2017-03-17 (Fri, 17 Mar 2017)

  Changed paths:
    M Jenkinsfile

  Log Message:
  -----------
  use xvfb-run instead of Xvfb plugin