Add EdgeStatus with unit tests. Update GraphId to use level rather
than hierarchy. Add #define guards to baldr/thor.
Forgot one!
Remove unused code.
Merge remote-tracking branch 'origin/master' into dwn
Add linesegment2 tests.
Merge remote-tracking branch 'origin/master' into dwn

Conflicts:
	Makefile.am
Fix merge issue.
Merge pull request #15 from mapzen/dwn

Add EdgeStatus with unit tests