added completed GoWatchIt spice plugin with tests

### What does your Instant Answer do?

The Instant Answer grabs availabilities for movies and television shows from GoWatchIt.com

### What problem does your Instant Answer solve (Why is it better than organic links)?

It organizes all of the availabilities of a given movie or show in a convenient row of easy to understand options.

### What is the data source for your Instant Answer? (Provide a link if possible)

GoWatchIt.com API

### Why did you choose this data source?

We think that GoWatchIt.com's API

### Are there any other alternative (better) data sources?

We don't believe so!

### What are some example queries that trigger this Instant Answer?

watch [title], stream [title], [title] on demand

### Which communities will this Instant Answer be especially useful for? (gamers, book lovers, etc)

Movie lovers, and anyone curious as to where they can watch their favorite movies and TV shows.

### Is this Instant Answer connected to a DuckDuckHack Instant Answer idea?

No.

### Which existing Instant Answers will this one supersede/overlap with?

Potentially CanIStreamIt's instant answer, which seems included in this repo but not live on your site.

### Are you having any problems? Do you need our help with anything?

Everything seems go to go.

### What are the terms of use for the API? Will DuckDuckGo need specific authorization (e.g. an API key)? Are there any costs associated with API usage?

We will need to provide you with an API key. Please talk to our business team for details.

### Where did you hear about DuckDuckHack? (For first time contributors)

### What does the Instant Answer look like? (Provide a screenshot for new or updated Instant Answers)


Here's a screenshot:

![screen shot 2014-12-08 at 4 16 34 pm](https://cloud.githubusercontent.com/assets/3160383/5347449/94188068-7ef6-11e4-83d5-5ffff44afec5.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://duck.co/duckduckhack/design_styleguide)
[X] Verified that instant answer adheres to code styleguide (https://duck.co/duckduckhack/code_styleguide)
[X] Tested cross-browser compatibility

    Please let us know which browsers/devices you've tested on:
    - Windows 8
        [] Google Chrome
        [] Firefox
        [] Opera
        [] IE 10

    - Windows 7
        [] Google Chrome
        [] Firefox
        [] Opera
        [] IE 8
        [] IE 9
        [] IE 10

    - Windows XP
        [] IE 7
        [] IE 8

    - Mac OSX
        [X] Google Chrome
        [X] Firefox
        [X] Opera
        [X] Safari

    - iOS (iPhone)
        [] Safari Mobile
        [] Google Chrome
        [] Opera

    - iOS (iPad)
        [] Safari Mobile
        [] Google Chrome
        [] Opera

    - Android
        [] Firefox
        [] Native Browser
        [] Google Chrome
        [] Opera
I think all we need here is line 44? `watchable = movie || show`. The `if (movie && show)` seems redundant to me because either way you prefer the movie result if it's there, otherwise fallback to a show. 

One question though -- what if the query specifies which they prefer? We should probably look for that, (`DDG.get_query()` should help), and prefer whatever they specified, if they did