#1 Allow-suspension tag not in DTD

[Javier Kohen]

The allow-suspension tag is neither documented nor part
of the DTD, but nonetheless is required if any of the
task outcomes has the suspend attribute set to true.

The definition of the "job-definition" element should
be changed from:
<!ELEMENT job-definition (setup, first-task, task*)>

to:
<!ELEMENT job-definition (setup, first-task,
allow-suspension, task*)>

And the following element definition should be added:
<!ELEMENT allow-suspension (#PCDATA)>