Add Siri realtime occupancy info

[lassetyr]

Summary

Propagates the Occupancy-value from SIRI ET (SIRI 2.0 - which is very basic) to the Transmodel GraphQL-API.

Issue

closes #3167

[codecov-commenter]

Codecov Report

Merging #4180 (3b7b5b6) into dev-2.x (8867ccc) will increase coverage by 0.00%.
The diff coverage is 36.73%.

@@            Coverage Diff             @@
##             dev-2.x    #4180   +/-   ##
==========================================
  Coverage      48.90%   48.90%           
- Complexity     10000    10003    +3     
==========================================
  Files           1371     1372    +1     
  Lines          56282    56331   +49     
  Branches        6538     6543    +5     
==========================================
+ Hits           27523    27547   +24     
- Misses         26734    26760   +26     
+ Partials        2025     2024    -1     

Impacted Files	Coverage Δ
.../org/opentripplanner/ext/siri/TimetableHelper.java	2.16% <0.00%> (-0.10%)	⬇️
...transmodelapi/model/siri/et/EstimatedCallType.java	0.00% <0.00%> (ø)
...java/org/opentripplanner/model/TripTimeOnDate.java	13.04% <0.00%> (-0.20%)	⬇️
...opentripplanner/routing/trippattern/TripTimes.java	75.00% <25.00%> (-2.05%)	⬇️
...tripplanner/ext/transmodelapi/model/EnumTypes.java	99.59% <100.00%> (+0.01%)	⬆️
...ipplanner/routing/trippattern/OccupancyStatus.java	100.00% <100.00%> (ø)
...lanner/routing/vehicle_parking/VehicleParking.java	82.03% <0.00%> (-0.79%)	⬇️
...ph_builder/module/ned/MissingElevationHandler.java	95.27% <0.00%> (+1.57%)	⬆️
...aph_builder/module/OsmBoardingLocationsModule.java	71.69% <0.00%> (+3.77%)	⬆️
...g/opentripplanner/updater/GraphUpdaterManager.java	53.94% <0.00%> (+3.94%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8867ccc...3b7b5b6. Read the comment docs.