Bug 1019783 - Always display IMEI codes for all SIM slots r=Rik

(cherry picked from commit c329a67bafe60032820ab64b52c07c22eeff114e)

Conflicts:
	apps/communications/dialer/js/dialer.js
	apps/communications/dialer/test/unit/dialer_test.js
	apps/communications/dialer/test/unit/mock_mmi_manager.js