feature #4147 : management of a cipher symmetric key for content encryption  

A new directory is created (by default in SILVERPEAS_HOME_DATA) to contain some resources to protect. This directory is referred as the hidden silverpeas directory.
The cipher keys will be stored into it as hidden files.

Don't forget to merge also the branch feature-4147 in Silverpeas-Core and in Silverpeas-installer-package.