code: public static Set<Property> parsePropertyList(String value, Map<String, ? extends Vocab> vocabs,
        ValidationContext context, EPUBLocation location)
    {
      return parseProperties(value, vocabs, true, context, location);
    }
docs: Parses a space-separated list of property values, and report validation
  errors on the fly.
  
  @param value
  the value to parse.
  @param vocabs
  a map of prefix to vocabularies.
  @param context
  the validation context (report, locale, path, etc).
  @param location
  the location in the validated file.
  @return