Highlight resource parameters as functions

Now:
![standard](https://f.cloud.github.com/assets/224922/2384600/b11a8d18-a90f-11e3-898f-a648605aaa37.png)

With this PR:
![highlighted](https://f.cloud.github.com/assets/224922/2384601/b5eeba9e-a90f-11e3-973a-7a92db902bf6.png)

@bbatsov What do you think?