Without this, we have hardly any enforcement. This is why the schema
mistake fixed in the previous patches weren't spotted immediately.
The hard work was done by:
```
$ for f in lightning-*.json; do grep -v '^ "additionalProperties": false,' $f | bagto $f; done
$ for f in lightning-*.json; do sed 's/"properties": {/"additionalProperties": false, "properties": {/' $f | bagto $f; done
$ make fmt-schemas
```
Then checking where 'additionalProperties: true' had been turned to
false (we deliberately use it in some places where there are if
statements in the schema, or occasionally where there can be arbitrary
fields).
[Including doc/rpc-schema-draft.json update by Shahana]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Merge information from `*.request.json` & `*.schema.json`. Also consolidate remaining details from `*.md` files and create a single file in schemas folder.
