SeatGeek Sports - new IA

//cc @jagtalon @abeyang
This is a WIP, I still need to add the test files, test throughly cross-browser compatibility, ecc.
Anyway, template:

**What does your Instant Answer do?**
Returns upcoming sport events for a given team/performer (or also big sport events like Miami Heat).

**What problem does your Instant Answer solve (Why is it better than organic links)?**
It's faster than the organic links. It lets users easily see what are the upcoming sport events
for a given team or performer.

**What is the data source for your Instant Answer? (Provide a link if possible)**
[SeatGeek](https://seatgeek.com/)

**Why did you choose this data source?**
Because it's exhaustive, has a good API and we're already using it for concert events.

**Are there any other alternative (better) data sources?**
Don't think so

**What are some example queries that trigger this Instant Answer?**
"upcoming matches Milan", "events UEFA champions league", etc

**Which communities will this Instant Answer be especially useful for? (gamers, book lovers, etc)**
People who loves to watch sports, especially live!

**Is this Instant Answer connected to a DuckDuckHack [Instant Answer idea](https://duck.co/ideas)?**
There's an Asana task for it!

**Which existing Instant Answers will this one supersede/overlap with?**
No one

**Are you having any problems? Do you need our help with anything?**
Not so far :) 

**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?**
It's free!

**What does the Instant Answer look like? (Provide a screenshot for new or updated Instant Answers)**
![screen shot 2014-11-02 at 20 38 07](https://cloud.githubusercontent.com/assets/3652195/5076596/83869a7e-6e9c-11e4-8280-4c37279df2b4.png)


## Checklist
Please place an 'X' where appropriate.

```
[x] Added metadata and attribution information
[] 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
        [x] Google Chrome
        [x] Firefox
        [] Opera
        [] IE 8
        [] IE 9
        [] IE 10

    - Windows XP
        [] IE 7
        [] IE 8

    - Mac OSX
        [] Google Chrome
        [] Firefox
        [] Opera
        [] Safari

    - iOS (iPhone)
        [] Safari Mobile
        [] Google Chrome
        [] Opera

    - iOS (iPad)
        [] Safari Mobile
        [] Google Chrome
        [] Opera

    - Android
        [] Firefox
        [] Native Browser
        [] Google Chrome
        [] Opera
`!api_result` should come before `api_result.error` because it will cause an error if `api_result` is empty or if it does not exist.