change in SQLDirectory: csv instead of sql

Hi,

Because there were problems with the portability of sql scripts among different sql engines, I have changed 
org.nuxeo.platform.ecm.directory.sql to create the tables based on the schema description and to populate them from csv 
files.
The csv file must have as a first line the list of column names separated with 
comma.

Also I renamed attributes "sqlScript" to "dataFile" and "executeScriptPolicy" with "createTablePolicy" in the directory 
configurations.