Re-arrange imports in sidebar/index.js

Keep the structure of having modules at higher layers (ie. with more
transitive dependencies) in the app nearer the top of the list by moving
the store registration to the bottom.

src/sidebar/index.js

@@ -184,8 +184,6 @@ module.exports = angular.module('h', [
   .directive('spinner', require('./directive/spinner'))
   .directive('windowScroll', require('./directive/window-scroll'))
 
-  .service('annotationUI', require('./store'))
-
   .service('analytics', require('./services/analytics'))
   .service('annotationMapper', require('./services/annotation-mapper'))
   .service('api', require('./services/api'))
@@ -210,6 +208,10 @@ module.exports = angular.module('h', [
   .service('unicode', require('./services/unicode'))
   .service('viewFilter', require('./services/view-filter'))
 
+  // Redux store
+  .service('annotationUI', require('./store'))
+
+  // Utilities
   .value('Discovery', require('../shared/discovery'))
   .value('ExcerptOverflowMonitor', require('./util/excerpt-overflow-monitor'))
   .value('OAuthClient', require('./util/oauth-client'))