While its fellow Canadian broadcasters converted most of their transmitters to digital by the Canadian digital television transition deadline of August 31, 2011, CBC converted only about half of the analogue transmitters in mandatory areas to digital (15 of 28 markets with CBC Television stations, and 14 of 28 markets with Télévision de Radio-Canada stations). The CRTC reported that the population in what two cities were no longer profitable for their operations and recommended terminating broadcasts?