Attempt to fix distance and score calculations
Update the Tracker model so it saves itself
Store Coordinates objects instead of Position

A Position just has coords and timestamp attributes, and we're not using the
timestamp anyway. A Coordinate has latitude, longitude, and accuracy
attributes like the server expects.
Fix regression with distance and efficiency calc
Update Map view as GPS data changes

The HUD was updating, but the map wasn't.
Minor code formatting tweaks, round "distance"
Merge pull request #43 from routemaster/issues/update-map

Update Map view as GPS data changes
Add a favicon
Merge pull request #45 from routemaster/favicon

Add a favicon
Merge pull request #46 from routemaster/features/submit-route

Features/submit route
Merge branch 'master' into features/horizontal-swipe
Refactor nav bar and swiping code

The majority of the swiping work now happens in a new `navBar` module.
Minor bug fixes have been added as well, mainly involving restoring of
the vertical scrolling position and ordering of calls to `render`.