Updating/Destroying a Weigh-in redirects back to the person it belonged to
Corrected sorting so it properly sorts. Renamed Person#week_difference to Person#recent_difference
Removed unused routes
Fixed up weigh-in's edit view so it goes back to the correct page
Added weigh-in form to the show person view.
Merge pull request #4 from Krushr/master

Removed some weigh-in routes and fixed sorting