assemble/handlebars-helpers — pull request #70 by supersheep (2013-09-27 15:01:20+00:00)
Title: deep clone array inside withSort helper, in case the origin data is affected

withSort should just sort data to be output, not the origin data.
For the case, I write

```html

{{#withSort pages "data.index"}}

{{titleize data.title}}

{{/withSort}}

```
with three page templates as below
```html
---
title: Home
num: 0
---
{{md 'README.md'}}
```

```html
---
title: Layout
num: 1
files: ['content/layout/*.md']
---

{{title}}

{{#each files}}
{{md this}}
{{/each}}
```

```html
---
title: Components
index: 2
files: ['content/components/*.md']
---

{{title}}

{{#each files}}
{{md this}}
{{/each}}
```

if the withSort directive sort the origin array, the grunt task will output

```
Assembling _site/components.html OK
Assembling _site/layout.html OK
Assembling _site/components.html OK
```