Improve Template parameter escaping
When creating a new application from a Template (ex. BasicService), parameters are passed as a single '&'-separated string from the UI to TemplateRestImpl.createApplication(String params).
Therefore parameters can't contain '&', and other nastier problems due to bad escaping.
Solution : at least manually encode / decode each param on both sides, or on server-side let FraSCAti do the escaping by rather passing a Map-like argument, or even better on client side find a more automated way (implementation.widget, see helloworld-widget example ?)