Usability improvements for the routing info box.

Implement some of the suggestions mentioned in
https://advancingusability.wordpress.com/2011/03/06/turn-left-in-700m/
- Show distance as string next to turn type icon
- Larger destination icon (based on flag.svgz from oxygen). Change
above should make its purpose clear.
- Left aligned instruction text
- No transparency in background (still not sure if that should stay,
waiting for feedback from others)
- Align icons to top/bottom

(cherry picked from commit 07b35fb00aa9d5e709e2590a5efd85105471cea7)

D +- -- src/icons/flag.png