Rename dividing decimals to dividing decimals 4
Retitle file
Dividing an integer by simple decimal
Include decimals representing mutliples of a quarter
Dividing decimals 3 exercise
Start dividing decimals 2
lint on solid_geometry, created volume_1
Rewrite rectchart to take an optional stroke

Like

```
rectchart([2, 3], [BLUE, null], 0, [null, GRAY]);
```

Auditors: eater
Fix shifting_and_reflecting_functions

I have no idea how this was working before, it seems to me like it would
have forced regeneration before and frozen things...

Auditors: alpert
Fix up radio, add some more unit tests

Summary: Make radio actually act the way it's supposed to

Test Plan: Run the tests, see that they work.

Reviewers: alpert

Reviewed By: alpert

Differential Revision: http://phabricator.khanacademy.org/D3300
Tweak styles so that <form> contains the problem

Auditors: jakesandlund
Ensure the correct answer is always a choice

Auditors: emily
ensure that one of the numbers has a imaginary component

example: [adding_and_subtracting_complex_numbers.html?seed=120](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/adding_and_subtracting_complex_numbers.html?seed=120&problem=0&debug)
improve hints: fix #58118
consistent punctuation

end sentence with a punctuation
add missing closing span tag, fix: #58083
Change answer type to regex
Use expression editor for complex number questions
Remove complexRegex function as it's not needed any more
Merge remote-tracking branch 'upstream/master' into div-dec