private Map<String, Object> fromJson(String json) {
        @SuppressWarnings("unchecked")
        final Map<String, Object> parsed = (Map<String, Object>) Json.fromJson(json);
        return parsed;
    }
Returns the meta data as a String that shall be used to build up the
complete Project meta data. If no metadata exists, returns an
empty optional.

@return the meta data or empty if none exists for this session
runtime-parent/runtime-application/src/main/java/com/speedment/runtime/application/AbstractApplicationMetadata.java