Crm 13964

Changes committed for CRM-13964
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1 'Pending in Cart' not visible when enable_cart setting is False.
2 Balance owed added to offline receipt when participant status is 'Partially Paid'.
3 Done Button added on view payment page.
4 Form.submit event on 'Register Participant' changed to submit button onclick.
5 Pop up alert in 'Register Participant' smarty translated.
6 Replaced addsetting method for variable partiallyPaidStatusId to assign to use in tpl. 
7 Popup status change fix.