Layout simplifications and tweaks

Layout simplifications and tweaks

Changes:
- Remove OrientationBuilder usage and landscape widget layout, as
  it complicates further rework due to not being as easily tested,
  and will be an ongoing maintenance hassle until landscape mode is
  actually required.
- Simplify layout by removing the arrows for tire pressure, and
  replacing the heavy Positioned usage with Row/Columns with some
  alignment directives.
- Swap the fuel and speed gauges to have the speed on the left, as
  that matches the typical cluster postion.
- Correct the aspect ratio of hero car image and increase its size
  to better fill available area.
- Tweaked label alignment and positioning on the temperature widgets
  to better make use of the available space.
- Corrected labels to 'km/h' in a couple of places.

Bug-AGL: SPEC-4660

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I45a15e2c4c9aa835745c754952979cda8baa90fa