The launch in India of a new BlackBerry by Research In Motion Ltd is not just a nod to its lower-end users who love it less for its security, push email and seamless roaming than for its simplicity and its Messaging. It's a strategy the Canadian company hopes will help fill both a hole in its balance sheet and a half-year wait for its next big thing - the BlackBerry 10 platform. But will it work? The handset itself won't impress devotees: …