An ODK Entities support to OdkCentral.py

[spwoodcock]

Is your feature request related to a problem? Please describe.

Following on from issue #206
And discussion #213

We have made some good headway for loading entities directly via ODK Collect intent: hotosm/odkcollect#2

We need to add support in osm-fieldwork and FMTM for generating the actual Entities for features in ODK Central, so that Collect can load the entities.

Describe the solution you'd like

The original issue has the conceptual model wrong.
The correct way to view this would be:

Projects are linked 1:1 to FMTM project.
Datasets are linked 1:1 to FMTM tasks.
Entities are linked 1:1 to FMTM (OSM or otherwise) Features within a task.

Entities are the likely way forward for FMTM, based on discussions with the ODK devs and internal discussions.

Previous flow

1. Create project.
2. Create task (with subdivided map features).
3. Upload form for task, with XForm id, name and upload media fields updated.
4. Upload a geojson for task/xform with the features to map.

New flow

1. Create project.
2. Create task (with subdivided map features).
3. Upload form defining entity dataset.
4. Upload CSV containing geometries in JavaRosa format, instead of geojson attachment
5. ... todo

Describe alternatives you've considered

With the modification to ODK Collect linked above, we could actually skip using entities entirely.

Instead we could load the XForm in Collect with the building pre-selected.

But in order to maintain the best compatibility with ODK going forward, and have the highest likelihood of a contribution being accepted, we opted to use Entities instead.

Additional context

Info about entities usage after research will go here: https://github.com/hotosm/osm-fieldwork/blob/main/docs/about/odk-entities.md

Very helpful code for converting WKT to Java Rosa geometry format (required in the entity csv file): https://github.com/ivangayton/ODK_geotrace_to_WKT

[spwoodcock]

[spwoodcock]