add I18n.reload! to make rake spec pass
move I18n translations to Grape::Exception::Base
rename Grape::Exceptions::ValidationError to Grape::Exceptions::Validation
I18n support for all Grape exceptions
spec pass for Rack 1.5

In Rack 1.5
Rack::Utils cookie functions now format expires in RFC 2822 format
Merge branch 'i18n' of github.com:niedhui/grape into merge
Rewritten spec to use cookiejar.
Updated CHANGELOG.