Feature/vik/oe ui

* Fix open ended grading javascript so multiple modules can be in the same vertical.
* Fix peer grading module javascript to scope locally.
* Fix rubric javascript to scope locally.
* Remove respond to feedback option.
* Display rubrics separately.
* Add in check mark indicators for rubrics.
* Allow collapse/expansion of rubrics.
* Add in a next step button for multistep problems.
* Remove annoying rubric parsing errors.
* Remove the get_submission_eta that would poll the grading server locally.
* Don't show feedback to students until they do the required number of peer gradings.
* Improve javascript by pulling out selectors.
* Enhance look and feel of module by redoing CSS and HTML in accordance with Marco's wireframes.
* Fix error with missing peer grading modules.
* Only show notification icon for needed staff/peer grading.

@jinpa @sefk @shnayder This is the mostly finished UI fix branch for peer grading.  We will be making some functional/visual tweaks, but wanted to get your overall impressions.  This is pretty close to being merge-ready.

## Enter an essay:

![peer grading start](https://f.cloud.github.com/assets/913340/934914/f440f8c8-0074-11e3-9343-0d8fdb8554d0.png)

## Submit essay for scoring:

![selection_002](https://f.cloud.github.com/assets/913340/934916/025e8ff6-0075-11e3-8080-2f10f681a4f6.png)

## Score the essay:

![selection_003](https://f.cloud.github.com/assets/913340/934918/0922c3a2-0075-11e3-9b44-f406d9a016f4.png)

## Score+Feedback from grader 1:

![selection_004](https://f.cloud.github.com/assets/913340/934921/0f2609c6-0075-11e3-91b4-a5ee4d19794a.png)

## Score + feedback from grader 2:

![selection_005](https://f.cloud.github.com/assets/913340/934924/182ccd52-0075-11e3-9061-61a83d4b2e36.png)

## Expand the rubric:

![selection_007](https://f.cloud.github.com/assets/913340/935404/a130fd46-0082-11e3-918d-176b4efcea55.png)

## Cannot yet see peer grading:

![selection_006](https://f.cloud.github.com/assets/913340/935159/8d01cd16-007b-11e3-96ac-491e03c12c45.png)