changes for spree 2.2 compatibility
add installation instructions
fix/cleanup translations
iva++
add tax_code to strong parameters whitelist
use I18n for error messages
adds specs support
adds specs for address model
Merge pull request #2 from kennyadsl/adds-specs

Adds specs
Merge pull request #1 from alepore/master

Updates for Spree 2.2 + Specs