Added tax_free field to Zone_model and view
When looking for matching zones during checkout also check the tax_free field (if valid VAT_number is provided)
Added translations
Add default tax zone data
Added checks for NL and !EU because choice of VAT rate does not depend on VAT-number
Added some additional setup instructions
Added spec for Address model

Spec is commented out and shows how the model should work. Spec doesn't work out of context of spree
Added warning message for setup README.md
Merge pull request #1 from Ultimaker/feature_1_set_tax_zones

Feature 1 set tax zones