[zanata/zanata-server] c35443: doc(CONTRIBUTING): fix checkstyle error

[GitHub]

  Branch: refs/heads/contributing
  Home:   https://github.com/zanata/zanata-server
  Commit: c35443aae415cb32fa99d63a8701bba28a7e7918
      https://github.com/zanata/zanata-server/commit/c35443aae415cb32fa99d63a8701bba28a7e7918
  Author: Ding-Yi Chen <dingyichen at gmail.com>
  Date:   2016-02-25 (Thu, 25 Feb 2016)

  Changed paths:
    M CONTRIBUTING.md

  Log Message:
  -----------
  doc(CONTRIBUTING): fix checkstyle error