Expire existing webadmin token so that the UI gets a new token

This is because we added a new appstore scope

migrations/20180807023917-expire-existing-tokens.js

@@ -0,0 +1,13 @@
+'use strict';
+
+exports.up = function(db, callback) {
+    db.runSql('UPDATE tokens SET expires=? WHERE clientId=?', [ 1525636734905, 'cid-webadmin' ], function (error) { // force webadmin to get a new token
+        if (error) console.error(error);
+
+        callback(error);
+    });
+};
+
+exports.down = function(db, callback) {
+    callback();
+};