[WAL-1635] Doc hstore_to_dict.
[WAL-1635] Doc hstore_to_dict.

opennode/nodeconductor-assembly-waldur,opennode/waldur-mastermind,opennode/nodeconductor-assembly-waldur,opennode/nodeconductor-assembly-waldur,opennode/waldur-mastermind,opennode/waldur-mastermind,opennode/waldur-mastermind