Feature 5518  : File sharing notification

Add notification capabilities when sharing file or folder. User can share file with internal plateform user or with external user using emails.
You can customize the notification content by editing models. The path which contains file and folder templates is
resources/StringTemplates/core/fileSharing/
This pull request also includes ney git commit from feature 5156.
This feature allow user to share files inside web formulary.
Be careful to get matching pull request on Silverpeas-Component repository.