Add missing options for Marshall component to Camel Editor Properties view

    <route id="currencies">
      <from id="_from4" uri="servlet:currencies" />
      <to id="_to1"
        uri="sql:select currencycode as code, currencyname as name from currencyexchange?dataSource=MyCamelDS" />
      <marshal id="_marshal2">
           <!-- note the library=json and prettyPrint options here -->
        <json library="Jackson" prettyPrint="true" />
      </marshal>
    </route>