Display scale current username above weight

[hgordon1]

The scale would be more easily used by multiple people in the same household, if the name of the current user always displayed directly above the weight, and this was clickable to change users. Too often early in the morning someone forgets to change, which user is about to step on the scale, and their weight is recorded under another person. Rather than having the names be in the drop-down in the upper right corner, move that to just above the weight, but have it default to whatever name was last used. That way, a different user stepping on the scale can see that they are about to do so and record Weight under a different user. They can then tap the name and change to themselves.