Temporary fix for DataMigrationBundle (untrack 'root' field)
Merge branch 'master' of git://github.com/AppVentus/DataMigrationBundle

# By Paul Andrieux
# Via Paul Andrieux
* 'master' of git://github.com/AppVentus/DataMigrationBundle:
  Add documentation about FosUserBundle limitation
  Add compliance with both get{Property} and is{Property}