20120309

Added two new “useless” modules:

• lino.utils.xmlgen.intervat is not yet being used by Lino, but it helped me to understand these XML Schemas, and lino.utils.xmlgen.intervat.validate was useful when implementing them in TIM.

• lino.modlib.vocbook will maybe some day become lino module, but currently it is usable only by people like me who are both Python programmer and French teacher. I have been using this code for more than a year when I needed to print vocabulary lessons for my students.