Add EPA Fuel Economy Fathead

**What does your Instant Answer do?**
Fathead for EPA Fuel Economy data.  Downloads source, parses it, and creates the standard output.txt file for fatheads.

**What problem does your Instant Answer solve (Why is it better than organic links)?**
-Displays city/hwy fuel economy directly.
-Gives ranges for city/hwy for models with multiple vehicle configurations
-Lists individual model configuration fuel economies.

**What is the data source for your Instant Answer? (Provide a link if possible)**
http://www.fueleconomy.gov/feg/epadata/vehicles.csv.zip

**Why did you choose this data source?**
Suggested in idea request

**Are there any other alternative (better) data sources?**
Not that I found with comprehensive fuel economy data.

**What are some example queries that trigger this Instant Answer?**
2011 Honda Fit fuel economy
2011 Honda Fit mpg (this could optional)

**Which communities will this Instant Answer be especially useful for? (gamers, book lovers, etc)**
Anyone researching mileage for a vehicle

**Is this Instant Answer connected to a DuckDuckHack [Instant Answer idea](https://duck.co/ideas)?**
Yes - https://duck.co/ideas/idea/4514/vehicle-fuel-efficiency

**Which existing Instant Answers will this one supercede/overlap with?**
None that I know of.

**Are you having any problems? Do you need our help with anything?**
How to best handle disambiguation pages and/or display is TBD.  For example, a search for "1993 Colt fuel economy" could reference 1993 Dodge Colt or 1993 Plymouth Colt.  Should the answer list links to those models or just list both models so no link is necessary?  For now, ambiguous redirects like this are simply deleted.

**Where did you hear about DuckDuckHack? (For first time contributors)**
jobs-subscribe@perl.org I believe.

**What does the Instant Answer look like? (Provide a screenshot for new or updated Instant Answers)**
http://withoutopus.org/fueleconomy.htm

## 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)
[] 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
        [] Google Chrome
        [] Firefox
        [] Opera
        [] Safari