Add field validation for datetime fields and option points.
Remove support in Javascript for "default" (empty) dates and update the template rendering script to support this in the JS tests.
Broadens the scope of the validation alert, and adjusts the editor height based on the alert height

Conflicts:
	openassessment/xblock/static/js/openassessment-studio.min.js
Added in animations
Merge pull request #565 from edx/grady/validation-sassafrass

Animations!
Make highlight field class less specific
Hide validation alert after validation is complete instead of before
Ensure that all validation errors are marked.
Fixup for template test case: ensure peer assessment has a date
Fixup: datetime field regression
Change validation highlighting to use a border instead of a color
Refactor integer field validation
Add field validation for peer assessment must grade and must be graded by.
Merge remote-tracking branch 'origin/authoring' into will/js-field-validation

Conflicts:
	openassessment/xblock/static/css/openassessment.css
	openassessment/xblock/static/js/openassessment-studio.min.js
	openassessment/xblock/static/js/src/studio/oa_container_item.js
	openassessment/xblock/static/js/src/studio/oa_edit_rubric.js
	openassessment/xblock/static/sass/oa/utilities/_developer.scss
Fixup: do not show NaN in student training labels
Update validation error message string.
Fixup: resolve merge conflict with sass
Merge pull request #570 from edx/will/js-field-validation

Will/js field validation
Update messages in authoring UI
Remove unsupported assessment configurations
Set default dates to something reasonable.