Added some error handling

Connection Refused error when pairing
Invalid pairing code if pairing code malformed
Add cucumber testing to bitpay library

Work done simultaneously with removing the client from the library

removed 'id' as an argument, no longer valid
Modified rake task to clear everything

Both before and after cucumbers.

Improved token clearance to use mongo

Rather than relying on capybara, deletes rather than revokes.
Remove bitpay client.

Bitpay client removed, bitpay bin for client removed.
Features modified to run with local token/key saved or not.
Rake task to clean up local files if created.
Rake task to run all tests, cucumbers, and clean up.

Move local file constants to the cucumber helper
Merge branch 'separated_client' of https://github.com/philosodad/ruby-client into philosodad-separated_client

Conflicts:
	README.md
	lib/bitpay/client.rb
Merge pull request#29 'philosodad-separated_client'