lob/lob-ruby — pull request #15 by bsiddiqui (2013-12-06 22:53:36+00:00)
Title: change USA to US in readme

The Lob API rejects USA as an invalid country code - this updates the README so people using the gem don't run into this issue:
```
{
"errors": [
{
"message": "The country you entered is not valid. Please ensure you are using the proper ISO-3166 country code"
}
]
}
```