CRM-13984 - Add help regarding use of receipt message, AND cleanup the Thank-you and Receipting form (move inline help strings to help pop-ups).

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* CRM-13984:
  https://issues.civicrm.org/jira/browse/CRM-13984
Merge pull request #4707 from davecivicrm/CRM-13984

CRM-13984 - Add help regarding use of receipt message, AND cleanup the T...