Modify invoice pdf to add names of users for every extension
Change the way we import users from LDAP according to the conversation with RSG and FPL this morning

Use of “description” field is not advised, and “buildingname” is totally discouraged.
Instead, for non-dni users we take the esUnileonDirectorioDescripcion field. For dni-users we use the usual “givenname”, “schacsn1” and “schacsn2” attributes

Added “processString” auxiliary function to deal with “de, del, y” particles in names