Updated readme with build instructions

Change-Id: I4fdb570d5479eceff566b0bc39d40546703ead57
Another take on build instructions

Change-Id: Ifa05c2027c0ada9c80ca3a1bb4d3740fadefb097
Fixed table layout on mobile

Change-Id: Ia755a43453820eda39cfc244441872834ad68a67