Fix walking route departure and arrival times
Note that this release includes the PR that centralizes constants -- which includes the promise cycle detection error, so this release is not stable!
- Walking start and end times reflect leave now and arrive by time queries
- Swagger docs have been updated to reflect correct request params
This release is currently deployed on transit-prod with transit-python:v1.0.7 and transit-ghopper:v1.0.7.