Resubmitting Steam Special

**What does your instant answer do?**
Fetch steam specials at Steam Store

**What problem does your instant answer solve (Why is it better than organic links)?**
Get to instantly know best Steam offers

**What is the data source for your instant answer? (Provide a link if possible)**
Official Steam Store (http://store.steampowered.com/)

**Why did you choose this data source?**
Steam api

**Are there any other alternative (better) data sources?**
No

**What are some example queries that trigger this instant answer?**
steam specials, steam offers

**Which communities will this instant answer be especially useful for? (gamers, book lovers, etc)**
gamers

**Is this instant answer connected to a DuckDuckHack [instant answer idea](https://duck.co/ideas)?**
Yes, [here] (https://duck.co/ideas/idea/976/steam-sales)

**Which existing instant answers will this one supersede/overlap with?**
 Steamdb perhaps

**Are you having any problems? Do you need our help with anything?**
 Apologies for resubmitting with a new pr, please close #859. Ty.

**\*\*Note:** Please attach a screenshot for new instant answer pull requests, and for pull requests which modify the look/design of existing instant answers.
![special_1](https://cloud.githubusercontent.com/assets/1424236/3209215/7279a7ec-ee60-11e3-87b9-21ee6c780ff0.png)
![updated_steam](https://cloud.githubusercontent.com/assets/1424236/3530548/94343eca-07a5-11e4-9580-5923ec993aa9.png)


##Checklist
Please place an 'X' where appropriate.

```
[X] Added metadata and attribution information
[X] Wrote test file and added to t/ directory
[X] Verified that instant answer adheres to design guidelines(https://github.com/duckduckgo/duckduckgo-documentation/blob/master/duckduckhack/styleguides/design_styleguide.md)
[X] Tested cross-browser compatability

    Please let us know which browsers/devices you've tested on:
      - Mac OSX
        [X] Google Chrome   
        [X] Firefox       
```

Please use `Spice.registerHelper` -- for now its just an alias but we plan on making it a little smarter in the future. Also for now please namespace your HB Helpers (ideally in the future you won't have to, but for now they're all created in the same scope). I.e. you should have:

```javascript
Spice.registerHelper("steamspecial_toDollars", function (cents) {
    ...
});
```