Merge pull request #161346 from pjmattingly/master

Updated khan-exercise to fix dependencies in 'congruency' utility
Keep the points in front!

I find it hard to believe I didn't catch this earlier...

Test Plan:
1. Load graphing_inequalities.html and graphing_inequalities_2.html in local mode.
2. Drag a point.
3. See https://s3.amazonaws.com/uploads.hipchat.com/6574/49847/XZzptRZSBkqtTAz/upload.png instead of https://s3.amazonaws.com/uploads.hipchat.com/6574/49847/jsNjObFKhW6nAHd/upload.png

Auditors: jack
Allow shading the area under a graphie-plotted function

Summary: Shading a parametric equation perhaps doesn't make a ton of sense by itself, but maybe it'll be useful.

Test Plan:
In graphie-to-png:

```
plot(function(x) {
    // Function to shade under
    return 0.03 * (x+5)*(x+2)*(x-3)*(x-6);
}, [-5, 3], // <-- x-range to shade
    false, true, { stroke: BLUE, fill: BLUE, opacity: 0.3 }
);

plot(function(x) {
    // Plot the entire function
    return 0.03 * (x+5)*(x+2)*(x-3)*(x-6);
}, X_RANGE);
```

Reviewers: jack

Reviewed By: jack

Subscribers: alpert

Differential Revision: http://phabricator.khanacademy.org/D8116
move header text addition to problem-template.handlebar

Summary: This is the companion commit to http://phabricator.khanacademy.org/D8419 which makes header text appear for both Perseus and old style exercises.  It removes the code from khan-exercise.js which added psych. intervention header text, since headers are now added in problem-template.handlebar instead.

Test Plan: ran on local dev_appserver

Reviewers: colinfuller, mattfaus, alpert

Reviewed By: alpert

Subscribers: benjaminhaley, jace

Differential Revision: http://phabricator.khanacademy.org/D8501
substate kas / subkas
Merge remote-tracking branch 'upstream/master' into kline_equal_optimize