SOSHibernate should raise a specific exception if the hibernate configuration path is wrong

Current Situation

Example - path to the hibernate configuration file defined as parameter on an job:

• value=my_path/hibernate.cfg.xml
  • if this file not exists, correct error message will be raised
    • hibernate config file not found: ....
• value is empty or is a directory path instead of a file path
  • error message raised by SOSHibernate is not clear:
    • Content is not allowed in prolog

Desired behaviour

• SOSHibernate error message should clearly explains what has been misconfigured