CRM-13379 js, contribution form - generalise  button double submit protection and add to contribution.main to prevent double submits where people have no confirm page

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* CRM-13379: Delete mailing from Archived, next page is Find Mailings
  http://issues.civicrm.org/jira/browse/CRM-13379

Conflicts:
	js/Common.js
	templates/CRM/Contact/Form/Task/EmailCommon.js