Manually i18nize all of the minor exercises

Summary:
Manually make modifications to all the exercises for i18n. Most of the problems revolved around:

- Wrapping Strings in variables or graphies with `$._`
- `data-if`s in the middle of sentences, that needed to be pulled out around the entire sentence
- Strings that needed to be put into Plural objects for pluralization
- Decoupling strings from logic

Test Plan:
Visit the changed exercises. Make sure the question renders
correctly and there are no javascript errors. Take all the hints and make sure
nothing is rendered incorrectly. Do the translations into box language, and
make sure that everything from the languages is boxy.

Reviewers: csilvers, john

Reviewed By: csilvers

CC: alpert, eater

Differential Revision: http://phabricator.khanacademy.org/D2504