Fixed single quote escape highlighting

Before:
![screen shot 2014-10-28 at 4 21 22 pm](https://cloud.githubusercontent.com/assets/208855/4818880/8d97a5b0-5ef9-11e4-8523-ea20a5014ee0.png)

After:
![screen shot 2014-10-28 at 4 21 36 pm](https://cloud.githubusercontent.com/assets/208855/4818882/938287e2-5ef9-11e4-864a-52f90ef9994a.png)