Historical note: this was originally a series of several commits, spread out
over several weeks. They have been squashed together to make `git annotate`
work properly.
The original commits were:
* 91ab3934 <Will> 2021-01-25 21:16:42 -0800 Add raw API end event schemas into /data directory
* aae22f47 <Will> 2021-01-25 21:33:06 -0800 Remove non-data files
* 1092d4ca <Will> 2021-01-26 20:41:33 -0800 Add data-compatiuble extension (.yaml) to all data files that currently omit one
* 21060109 <Will> 2021-01-26 20:57:28 -0800 Remove symlink to event-schemas, and update openAPI schema paths accordingly
* 4f633845 <Travis Ralston> 2021-04-12 21:54:54 -0600 Fix event schema examples too
* 301c7b2f <Will> 2021-02-05 10:15:42 -0800 Restore docs describing OpenAPI extensions that we use
This is a mix of Synapse and Dendrite behaviour, mostly Dendrite. Synapse returns `null` for field values that aren't set, however Dendrite just doesn't return them and instead opts for an empty object.
Further, synapse is lacking in error codes in this area. Dendrite does some additional validation on this API which introduces more errors for bad requests, instead of defaulting to empty objects/200 OK responses.
Likewise, Dendrite returns a 404 when the user is not found while Synapse returns 200 OK/empty object.
