CRM-12277 Add info to Batch status change message to let users now that notifications will be sent for Pending Pay Later to Attended or Registered updates.

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* CRM-12277: Notify batch Change Participant Status users that changing status FROM Pay Later TO Attended or Registered triggers email notification and payment status update
  http://issues.civicrm.org/jira/browse/CRM-12277
Merge pull request #321 from davecivicrm/CRM-12277

CRM-12277 Add info to Batch status change message to let users now that ...