Need to document all of the common exceptions that occur,
in a way that will help our users. We get a good portion
of questions from users not knowing how to interpret these
errors. (Of course, it would be better to have clearer error
messages.)

Common exceptions are InvocationTargetException and
NullPointerException. Need to document:

   Exception name
   - Technical cause and description of exception
   - Workarounds and solutions