Fix delete link for taxonomies

since the Delete taxon url is look like this,
DELETE "/api/taxonomies/854451433/taxons558398399"
the delete process is not happening.
somebody missed a slash in between the 'taxon' and taxon_id

Fixes #2710
Mailers now require a from address, so we need to give defaults, using MailMethod.current

Conflicts:
	api/spec/controllers/spree/api/v1/shipments_controller_spec.rb
	core/app/models/spree/app_configuration.rb
Truncate product description when used as meta description

Fixes #2396
Fix jirafe admin settings styling

Fixes #2733
Move currnet_currency and ip_address helpers to ControllerHelpers::Order, where they're required
[frontend] tidy up let(:order) block in CheckoutController spec
Correct MailMethod usage in mail_interceptor, order mailer and shipment mailer specs
Added checked values for the radio_button_tag of currency_symbol. fixes #2755

Fixes #2756
Fix value of back_to_properties_list in en.yml

Fixes #2753
Don't require payment methods if payment isn't required