Fix: rewrite no-spaced-func rule (refs #1212)

Before:

```
$ npm run perf

> eslint@0.7.4 perf /Users/michael/projects/eslint
> node Makefile.js perf

CPU Speed is 2600 with multiplier 7500000
Performance Run #1:  1618.9791850000001ms
Performance Run #2:  1584.846229ms
Performance Run #3:  1643.8295779999999ms
Performance Run #4:  1608.190126ms
Performance Run #5:  1620.71616ms
Performance budget ok:  1618.9791850000001ms (limit: 2884.6153846153848ms)
```

After:

```
$ npm run perf

> eslint@0.7.4 perf /Users/michael/projects/eslint
> node Makefile.js perf

CPU Speed is 2600 with multiplier 7500000
Performance Run #1:  1577.5375589999999ms
Performance Run #2:  1616.653781ms
Performance Run #3:  1515.187082ms
Performance Run #4:  1508.76889ms
Performance Run #5:  1515.655062ms
Performance budget ok:  1515.655062ms (limit: 2884.6153846153848ms)
```