Merge "Docs: Adding information to Building-for-Billions landing page. am: cbaf3f9986 am: 2663c419c0 am: 7208e94355" into cw-f-dev am: b0da43c8f2
am: 26ee5e81c7

Change-Id: I2b0ab6d57a67c351056813143002992078a89a3f