Add stop to stop transfer unit tests
Put graph creation in singleton to speed up unit test
Add arrive-by transfer unit test
Let trip 15.1 have a frequency defined from 14:00:00 to 18:00:01 instead
of from 14:00:00 to 16:00:01
Fixed small bug where time was not updated correctly with minimum
transfer times in combination with frequency-based trips
Add unit tests for transfers in combination with frequency-based trips
Merge pull request #1168 from jkoelewijn/transferStopToStop

Transfer stop to stop