By Poornima Gupta and Ben Berkowitz (Reuters) - Tim Cook wants investors to "think different" about Apple: less as a hyper-growth startup-like company and more as a mature but robust technology corporation with the world's most lucrative dividend. If Wall Street follows Apple's famous advertising slogan of old, it may relieve some of the pressure on Apple's chief executive, quiet investors' grumbling about its recent share price slide, and buy the company time to do what it says it does best: come up with and market new products. ...