Add gauge lib and gauge widget view/template

Update: There is a weird loading bug, which has been documented on the
internets, that has a workaround involving loading Raphael before
loading RequireJS. I am employing this workaround until I can find a
better solution to the loading of Raphael/JustGage.

Change-Id: I1c01a49dc679260d48c1ba459e568bc85d886258