Update cookies page

Includes:
- new content
- added option to turn analytics on/off
- non-js version for the on/off switch
- a banner to confirm user's choice was saved,
  shown when they click the save button
- the cookie banner that appears on all other
  pages removed from this page

app/assets/stylesheets/govuk-frontend/_all.scss

@@ -25,6 +25,7 @@ $govuk-assets-path: "/static/";
 @import 'components/back-link/_back-link';
 @import 'components/button/_button';
 @import 'components/details/_details';
+@import 'components/radios/_radios';
 
 @import "utilities/all";
 @import "overrides/all";

app/assets/stylesheets/main.scss

@@ -82,6 +82,7 @@ $path: '/static/images/';
 @import 'views/send';
 @import 'views/get_started';
 @import 'views/history';
+@import 'views/cookies';
 
 // TODO: break this up
 @import 'app';

app/assets/stylesheets/views/cookies.scss

@@ -0,0 +1,17 @@
+.cookie-settings__form-wrapper {
+  display: none;
+
+  .js-enabled & {
+    display: block;
+  }
+}
+
+.cookie-settings__no-js {
+  .js-enabled & {
+    display: none;
+  }
+}
+
+.cookie-settings__confirmation {
+  display: none;
+}