Add new API cancelRequest to CMWeatherManager. This will allow
clients to cancel a request that was previuosly submitted to
the weather service.
As part of this change, requestWeatherUpdate(weatherLocation),
requestWeatherUpdate(Location) and lookupCity(cityName) will
now return the RequestInfo object created if the request
was successfully submitted to the weather manager service
TICKET: CYNGNOS-2383
TICKET: CYNGNOS-2385
Change-Id: Ic122f91e0ea8a24d81dbed48741ef1e33567b56c