Move similar methods together.
Remove some reference to flat profile.
Remove reference to EPS.getMaxSlope()
Remove reference to getElevationProfileSegment()
Remove references to EPS.getSlopeXxx()
Remove reference to getElevationProfileSegment()
Remove override of removed function.
Merge ElevationProfileSegment to StreetWithElevationEdge.
Split elevation profile by caller.
Remove partial getElevationProfile from StreetEdge.
Refactor GraphService. Add GraphSource.
Add GraphServiceImpl unit testing.
Use File to extend paths.
Extract path to input stream code from loading.
Load graph from classpath.

Note: This code is a bit useless for now as the primary
goal of loading graph from classpath was to embed graphs
in webapp WAR files. As long as we do not support webapp
containers this class is probably useless.
Add @Override to overriden method.
Add unit-test for file-related graph service methods.
Do not register graph when problem loading.
Add throws clause to getGraph(...) methods.
Allow call to reloadGraph in memory graph source.