Remove StockMovements#new

I broke this page over a year ago in
0f5c0d0

Nobody noticed so it should probably be safe to remove.

This page previously provided an interface to manually create a stock
movement. I think this can more easily be done by editing stock from our
stock management page.

backend/app/assets/javascripts/spree/backend.js

@@ -57,7 +57,6 @@
 //= require spree/backend/stock_management/index_add_forms
 //= require spree/backend/stock_management/index_update_forms
 //= require spree/backend/stock_management/stock_item
-//= require spree/backend/stock_movement
 //= require spree/backend/stock_transfers/count_update_forms
 //= require spree/backend/stock_transfers/edit
 //= require spree/backend/stock_transfers/receive

backend/app/views/spree/admin/stock_movements/index.html.erb

@@ -4,12 +4,6 @@
 
 
 <% content_for :page_actions do %>
-  <% if can?(:create, Spree::StockMovement) %>
-    <li>
-      <%= button_link_to Spree.t(:new_stock_movement), new_admin_stock_location_stock_movement_path(@stock_location), id: 'admin_new_stock_movement_link' %>
-    </li>
-  <% end %>
-
   <% if can?(:display, Spree::StockLocation) %>
     <li>
       <%= link_to_with_icon 'arrow-left', Spree.t(:back_to_stock_locations_list), admin_stock_locations_path, class: 'button' %>

backend/config/routes.rb

@@ -167,7 +167,7 @@
     end
 
     resources :stock_locations do
-      resources :stock_movements, except: [:edit, :update, :destroy]
+      resources :stock_movements, only: [:index]
       collection do
         post :transfer_stock
         post :update_positions