BS-6760
Do not import jar in dependencies if sources are available.
Import of actor filters was ran twice.
Fix invalid confirmation/error messages

Conflicts:
	bundles/plugins/org.bonitasoft.studio.actors/messages.properties
	bundles/plugins/org.bonitasoft.studio.actors/src/org/bonitasoft/studio/actors/ui/handler/ImportActorFilterHandler.java
	bundles/plugins/org.bonitasoft.studio.connectors/src/org/bonitasoft/studio/connectors/handler/ImportConnectorHandler.java
	bundles/plugins/org.bonitasoft.studio.connectors/src/org/bonitasoft/studio/connectors/repository/ImportConnectorArchiveOperation.java