Eliminate short spurs that can be cleanly removed

Two categories of short spurs, offshoots of straight lines and short
spurs on longer spurs, are now cleanly removed.
Merge pull request #79 from mojotech/fcanas/spur-reduction

Eliminate short spurs that can be cleanly removed
Tune number pad animation
Fix type in Route to accept Obj-C-origin arrays
updated unit button to display "miles / km" fixed #71