edx/edx-ora2 — pull request #365 by wedaly (2014-05-27 19:08:34+00:00)
Title: Will/ai grading xml rules

[TIM-589](https://edx-wiki.atlassian.net/browse/TIM-589)

* Provide a default value for the algorithm ID
* Validate that the algorithm ID is set to "ease"
* Validate that example-based assessment does *not* provide start/due dates
* Support just AI configuration (no self- or peer-assessment)
* Validate example-based assessment criterion options have distinct point values.

I also refactored the tests a bit and added some tests for example-based assessment deserialization.

@stephensanchez @gradyward