New ask geo api

I have updated the gem to include the changes required by AskGeo as they are now deprecating their old API which will cease to function next month.  I have also updated the gem and specs to work with the slightly different API results that they return now.

Since this is a breaking change it should likely be in a major version release of the Gem.  However, you may choose to force people to switch since the old API will actually be turned off whether they update the gem or not.

See : http://askgeo.com/new_version

From their email :

````
Dear AskGeo User,

(If you are a paying customer, you will already have received a separate email.  If you are a paying customer and did not receive a separate email, please email me at this email address and I'll follow up.)

We are excited to announce a number of improvements to the AskGeo Web API, as well as some changes that will require that you update your code to transition to our new API.

First, the improvements.

Improvements and Additions to the AskGeo Web API
We have transitioned away from Google App Engine, which had been causing us a lot of trouble, and are now hosting with Amazon Web Services (AWS).  We have had a lot of experience with AWS and are confident that this change will lead to lower latency and higher reliability.
We have added a number of additional databases to our offerings.  Now, in addition to the time zone database, we also offer 7 additional databases based on data from the US Census Bureau.  For locations within the US, given a latitude and longitude, you can now query detailed information about state, county, county subdivision, census tract, census block, city, and ZIP code.  The new information includes more than 250 statistics about the residents of each of the geographic entities in our databases, including details about sex, race, age, income levels, real estate values, and job type. 
The US Census APIs can also be used as a city-level reverse geocoding API within the US, providing city, state, and ZIP code for a given location.
We have updated the API to allow querying more than one database with a single web request.
Transitioning to the New Web Site

The old servers will be shut down on May 31st, 2012. For instructions on how to transition to the new servers, please see:

http://askgeo.com/new_version

In short, you'll need to sign up for an account on the new server, and get a new API access key.  The API URL has also changed slightly.  We will continue to support the old response format from the old web API, however we also encourage you to switch to the new API completely.  Documentation for the new API is located here:

http://askgeo.com/#web-api

Changes to Subscription

In launching the new site, we have made some minor changes to the subscription.  Rather than place usage restrictions (such as a maximum number of requests per minute), we simply say that the $200 fee gets you up to 20 million requests in a year.  In the unlikely event that we have a user that uses more than 20 million requests in a year, they will need to purchase an additional $200 refill.  

We will also continue to offer conditional free access to some non-profit organizations, open-source projects, and researchers.  Please see the "Free Access to the Web API" section of:

http://askgeo.com/#pricing

The main change is that the old site defaulted to giving everybody free access while requiring commercial users to voluntarily pay.  The new site requires that qualified users request free access.  We understand that this added barrier will be an inconvenience to legitimate free users, but we found that too many commercial entities were taking advantage of our previous policy.

As always, if you have any questions, feel free to write to this email address or to feedback@askgeo.com.

Best Regards,
The AskGeo Team
````