mod_rest: Fixup internal schema references for correctness With JSON Pointer support in util.datamapper, it is now possible to use the schema file as-is without the fixups mod_rest does.

This module blocks configured queries that change server state.

E.g. to make vCard storage read-only:

``` lua
readonly_stores = {
	vcard = { "vcard-temp", "vCard" };
}
```