Fix bad colorization of several functions

The functions format, local, url, attr, counter and counters were being colorized wrongly so I fixed it by grabbing the solution adopted for the language-css package.

Before:
![before](https://cloud.githubusercontent.com/assets/1958425/5328763/2455d4d2-7d85-11e4-9cd6-2001de76b828.png)

After:
![after](https://cloud.githubusercontent.com/assets/1958425/5328764/298fdba0-7d85-11e4-8bd4-951adc549a00.png)