$imports (JSON array of objects) : used to import Types located in other Schema Documents (i.e., in other Namespaces). Imports are not recursive, i.e., importing a Schema Document does not import the further Schema Documents that it may itself import.
Each JSON object in this JSON array has the following properties:
$namespace (JSON string): the namespace in which the Types being imported live.
$location (JSON string): a hint about where to find the Schema Document for this namespace.
$prefix (JSON string): the prefix used in Qualified Names to refer to Types in the above namespace. Must not contain a colon.
$types (JSON array of objects representing Types) : the Types defined in this document. How these objects look like is explained in subsequent sections.
