Discussion about the task model

[svogt]

This issue is used to track discussion about the task model. Please feel free to add comments.

Attachment:
* adding a MIME-type attribute
* I did a quick search and did not find an existing ecore-model for MIME-types. The question is if we need such a thing. I think it's up to the client to propose or set a sensible mime-type as well as use that to display the data.

States and Transitions:

• The current model does not support creating multiple task types that share common states with different state transitions. Is this an important use-case, or do we simply not share state instances across task types?

[BryanHunt]

I've made some modifications to the task domain model that will hopefully address the concerns of shared states with different transitions. https://github.com/BryanHunt/eTrack/wiki/Task-Domain