Divert perseus issue reports to JIRA instead of GitHub

Testing out a different platform for issue tracking that will hopefully make it easier to get issue reports directly to content creators. We'll see how this goes.

Test Plan: With the corresponding changes in webapp, report an issue on a khan-exercises problem and a perseus problem. In each case, see that the issue gets created in the appropriate tracker.

Auditors: alex
Make inscribed polygons exercise more lenient
Add extra domain requirement when dividing by x
Remove assumption in question
Add getClockwiseCoords to MovableAngle for interactive-graph angle grading

Test Plan:
 * test.html add in interactive-graph
 * add an angle
 * try grading with the coordinates in both positions
   (normal and flipped, but with the angle measure correct)

Auditors: alex, eater
Merge pull request #156673 from petercollingridge/constructions2

Make inscribed polygons exercise more lenient
Merge pull request #156705 from petercollingridge/sim-rat-exp-4

Add domain requirement to simplifying rational expressions 4 when needed
correct hint, fix #156972

move negative sign to the numerator
Merge pull request #157558 from mauk81/patch-4

correct hint, fix #156972
Merge pull request #155599 from mauk81/improve

hide arrowAtClipPoint
Add a message on "Check Answer" when empty

Summary:
Displays "It looks like you haven't answered all of the question yet."
to the student if they click "Check Answer" without having filled out
all of the question.

Hopefully this reduces the number of confused students who think the
website is broken (and the number of bug reports sent for not filling
in the whole question).

Test Plan:
 * python -m SimpleHTTPServer 7000
 * visit http://localhost:7000/exercises/factoring_linear_binomials.html
 * press "Check Answer" without filling anything out
 * answer the question and make sure it still works

Reviewers: eater

Reviewed By: eater

CC: alpert, alex

Differential Revision: http://phabricator.khanacademy.org/D5898
subkatex
Fix setting parseError in calculator

Summary:
Taken from D5922 until it's decided what to do with that.  Previously
the code was attempting to set an error handler which would allow the
calculator to catch any parse errors, since that was not set correctly,
any parsing errors (such as "(") cause a javascript error and scroll the
page to the top.

Test Plan:
* open an exercise with a calculator (like standard deviation)
* put some malformed input in, like 'sqrt(', hit enter
* the calculator should output 'err' and there shouldn't be a javascript error.

Auditors: alex