Importing WORK from another current project (agenda events)
- upgrading ICal4J API version
- adding a structure to develop entities and their repositories
- adding time unit conversion tools
- improving unit rounding conversion
- improving period tools
- adding a lot of stuff around useful Datable.java interface and their implementations
feature #907 sprint1 :   Enrich the javadoc and the Entity implements now the interface Serializable
Feature #907 - modifying javadoc of some classes and fixing the AbstractEntity.class equals method.
Feature #907 : adding new query methods into Silverpeas JPA repository API.
feature #907 sprint1 :   Add the mapping of the roles in Suggestion Box with the predefined roles in Silverpeas Core. Now, when a mapping doesn't exist for an application, by default the roles in the applications are those in Silverpeas Core
Feature #907 : refactoring request router mechanism.