Features/fields translations

Changes needed to translate fields from Zoho to Ruby and remember the proper translations, as explained in #29

This way, I can have an utm_campaing attribute in my Zoho and Ruby will remember that the original attribute is not called Utm Campaign but utm_campaign.

I have tested it with our application (not in production yet) But I couldn't run any spec because I don't have a usable Zoho API Key (the only one I have is populated with real data and I can't run specs over them). Is there any procedure to run specs without a real API Key?