Add a separate 'Description' property.
Currently, the already existing 'Comment' property is used to set the task subject and description. By introducing a Description property as well, we want to be able to set a separate task description if required. If the 'Description' property isn't set, we will still use the 'Comment' property (for backwards compatibility).
This involves changes in:
- human task handler to take the new property into account (mauricio)
- add 'Description' property by default in web designer (tiho)
- add 'Description' property by default in eclipse modeler (bob)