Added stripeAutomaticTax feature flag as private beta

This will be used to test the use of the Stripe Tax feature during
development. We want it behind a private beta flag so that we can
stick it in production without causing problems with payment systems
for existing sites.

ghost/admin/app/services/feature.js

@@ -71,6 +71,7 @@ export default class FeatureService extends Service {
     @feature('emailErrors') emailErrors;
     @feature('milestoneEmails') milestoneEmails;
     @feature('websockets') websockets;
+    @feature('stripeAutomaticTax') stripeAutomaticTax;
 
     _user = null;
 

ghost/admin/app/templates/settings/labs.hbs

@@ -252,6 +252,19 @@
                         </div>
                     </div>
                 </div>
+                <div class="gh-expandable-block">
+                    <div class="gh-expandable-header">
+                        <div>
+                            <h4 class="gh-expandable-title">Stripe Automatic Tax</h4>
+                            <p class="gh-expandable-description">
+                               Use Stripe Automatic Tax at Stripe Checkout. Needs to be enabled in Stripe
+                            </p>
+                        </div>
+                        <div class="for-switch">
+                            <GhFeatureFlag @flag="stripeAutomaticTax" />
+                        </div>
+                    </div>
+                </div>
             </div>
         </div>
         {{/if}}

ghost/core/core/shared/labs.js

@@ -37,7 +37,8 @@ const ALPHA_FEATURES = [
     'urlCache',
     'lexicalEditor',
     'websockets',
-    'webmentionEmails'
+    'webmentionEmails',
+    'stripeAutomaticTax'
 ];
 
 module.exports.GA_KEYS = [...GA_FEATURES];