Instructors can edit response feedback prompt text

Before, instructors were unable to edit the feedback prompt text ("I noticed that
this response...") displayed in the response box asking a student to provide feedback
on the peer responses they received.

To allow instructors to edit this, I've added an editable xml element (default_feedback_text).
The text within the element defaults to "I noticed that this response...," but an instructor
can change this text to whatever he or she wants by editing the text within the xml element.

Got rid of translation of none default text

Fixing error

Fixing error

Fix conflicts

Fixing syntax error

Adding feedback default text to authoring gui

Trying to fix issues with editing feedback default text

Fixing validation issues

Linking up javascript to pass new default text field

Not sure whats not working.. hmm.

Debugging JS problems

Compliled javascript

Using keyword args again

fixing validation errors

Cleaned things up
Got rid of stripping whitespace in python code. Try somewhere else.
Fixed almost all tests