Add customisable validation for otherwise optional elements in mzTab-M to conform to MetaboLights requirements

[nilshoffmann]

https://github.com/lifs-tools/jmzTab-m

This could be based on the existing BeanValidator or on the Validation infrastructure that is currently being used for the parameter based semantic validation.
The rules should be described in a machine readable format (either XML, as currently for the semantic mapping xml, or as JSON).

[nilshoffmann]

The HibernateValidator that is already present in the jmztab-m library could be used for that:

• XML: https://docs.jboss.org/hibernate/stable/validator/reference/en-US/html_single/#chapter-xml-configuration
• Programmatic: https://docs.jboss.org/hibernate/stable/validator/reference/en-US/html_single/#section-programmatic-api