feature : taxons meta tags and title

Fixes #2787

Conflicts:
	frontend/spec/requests/taxons_spec.rb
Fixes orders#show title for i18n cases

Fixes #2784
Remove ancient TODO from bottom of orders_controller_spec
When a calculator is using a preference of type :text, a textarea is shown. The calculator.js should disable/enable this textarea the same as the input from a preference of any other type.

Fixes #2782

Conflicts:
	backend/app/assets/javascripts/admin/calculator.js
Fix a missing icon class [Fixes #2638]

Fixes #2775
Reduce minimum characters required for variant autocomplete (from 4 to 3)

Fixes #2774
Add US Military state codes to default states

Fixes #2769
Wait a bit longer after update in promotion_adjustments_spec before adding an adjustment