added Crowdtilt::ApiError, fixed tests, and added tests to confirm Crowdtilt::ApiError stores response object for later inspection

increment version from 1.0.0 -> 1.0.1 since this should be backward compatible

require api_error from within crowdtilt.rb

fix dir structure so everything just needs to require lib/crowdtilt

update gemspec

use to_hash on incoming faraday responses to improve future swapability.

make handle_response require incoming `response` param to either respond_to?(to_hash) or have friendly hash-like responses to :status and :body keys.

whitespace fixes
Merge pull request #1 from Crowdtilt/add_api_error_exception_class

Add api error exception class