[Finishes #79484946] Free play links on student dashboard and puzzle headers

Links to the k1 version of Playlab and Artist free play when the user is in a k1 course.

![screen shot 2014-09-29 at 3 25 53 pm](https://cloud.githubusercontent.com/assets/413693/4450618/a12a4684-4827-11e4-83c8-b6cdf1cdc87c.png)

![screen shot 2014-09-29 at 2 37 00 pm](https://cloud.githubusercontent.com/assets/413693/4450623/afceaf36-4827-11e4-961d-3f893315baa3.png)

you can actually find the real course1 script, may be a more realistic test (seeding in test 'guarantees' that the real scripts exist, that's what you're testing with these tests anyway)
````
Script.find_by_name('course1')
````