Add parent error class that inherits from StandardError instead of Exception
Add parent error class that inherits from StandardError instead of Exception

By default Ruby's `rescue` without specifiying a specific Error class
will rescue `StandardError`s, which means that SmartyStreets errors will
fall through most `rescue` calls and may incidentally cause developers
to catch the `Exception` class which is bad practice.

http://stackoverflow.com/questions/10048173/why-is-it-bad-style-to-rescue-exception-e-in-ruby

russ/smarty_streets