Make Dlugosz int packer null-safe.
Remove CompactLineString instances, store byte[].

As suggested by Andrew.
This shaves off ~1.3% of graph size on street-data only graph.
Update CompactLineString with new version.
Implement a fast version of DirectionUtils.azimuth.

The default version is exact (take into account spherical geometry) but insanely expensive.
Replace with an equirectangular projection approxmimation (10 times faster and precise
enough for our purpose of computing nearest edges azimuth score (drive mode) and relative
directions from a 100m street to the next.

Benchmark for 1000000 computations:
- 5535 ms for the exact version
- 375 ms for the approximate version.
Add unit testing for DirectionUtils azimuth stuff.

Test performances, and non-regression (max error).