add configurable option to clone products without copying original images

Fixes #4711
Bump Rails to ~> 3.2.18
Bump activemerchant to 1.43.1

This should fix spree/spree_gateway#149
Lock capybara-accessible down to 0.2.0

0.2.1 causes this bug: https://github.com/spree/spree/pull/3414#issuecomment-47186627

Related to #3414
Optimize available_countries

Use .sort_by so that we only run .parameterize once per country.

Fixes #4899
use the variant_full_price on the product show page so the correct currency settings are used. Fixes #4995

Conflicts:
	frontend/app/views/spree/products/_cart_form.html.erb
fix failing specs with variant price

Conflicts:
	frontend/app/views/spree/products/_cart_form.html.erb
refactor the variant price for product.js.coffee. Thanks @gmacdougall

Conflicts:
	frontend/app/views/spree/products/_cart_form.html.erb
Validate uniqueness of order numbers... Why was this FIXME never fixed until now... Fixes #5102