Implement a "Fetch Directory Values" operation.

The goal of the operation is to return complete rows of directory entries, with the following parameters:

• Directory name
• Additional filtering instruction (a string, if the directory api already allows this, which I don't know)
• Translate Label : this parameter, if checked, would make a serverside resolution of the i18n label, if the directory implements the schema "vocabulary".
• optional : path of the document context => this will be used to fetch the right directory according the local configuration of the directory. => see NXP-6988