Function calls in spread attributes

[Try Coffee-React Link](https://jsdf.github.io/coffee-react-transform/?code=PGRpdiB7Li4uQHByb3BzLmZ1bmMoYSxiKX0gLz4%3D)

This compiles properly:

```
<div {...@props.func(a,b)} />
```

This does not (note the offending space between the `a,` and `b`):

```
<div {...@props.func(a, b)} />
```
