Don't allow to change hook's state while it's saving

assets/scripts/app/models/hook.coffee

@@ -23,6 +23,7 @@ require 'travis/model'
   ).property()
 
   toggle: ->
+    return if @get('isSaving')
     transaction = @get('store').transaction()
     transaction.add this
 

assets/scripts/app/templates/profile/tabs/hooks.hbs

@@ -19,6 +19,7 @@
       {{#each hook in hooks}}
         <li {{bindAttr class="hook.active:active"}}>
           <a {{bindAttr href="hook.urlGithub"}} rel="nofollow">{{hook.slug}}</a>
+          {{#if hook.isSaving}}<span class="loading"></span>{{/if}}
           <p class="description">{{hook.description}}</p>
 
           <div class="controls">