Fixed smart app banner bug

Author: emilbaehr

_config.yml

@@ -8,7 +8,7 @@ playstore_link                            :
 
 app_name                                  :                                           # Automatically populates if not set and if iOS app ID is set.  Otherwise enter manually.
 app_price                                 :                                           # Automatically populates if not set and if iOS app ID is set.  Otherwise enter manually.
-smart_app_banner                          : true                                      # Set to true to show a smart app banner at top of page on mobile devices.
+enable_smart_app_banner                   : true                                      # Set to true to show a smart app banner at top of page on mobile devices.
 app_description                           : Wherever some that and kiwi that well 
                                             dolphin alas this the mindfully jeepers 
                                             one aside canny one preparatory up less therefore 

_includes/head.html

@@ -4,8 +4,7 @@
 	<meta name="viewport" content="width=device-width, initial-scale=1">
 	<base target="_blank">
 
-	<title>{{ site.app_name }}</title>
-	<title>{% if site.title %}{{ site.title }}{% else %}{{ site.app.name }}{% endif %}</title>
+	<title>{% if site.title %}{{ site.title }}{% else %}{{ site.app_name }}{% endif %}</title>
 	<meta name="description" content="{{ site.description }}">
 
 	<!-- Favicon -->
@@ -15,8 +14,8 @@
 	<link rel="apple-touch-icon-precomposed" href="apple-icon-precomposed.png">
 
 	<!-- Smart App Banner -->
-	{% if site_enable_smart_app_banner %}
-	<meta name="apple-itunes-app" content="app-id={{ site.app_ios_id }}">
+	{% if site.enable_smart_app_banner %}
+	<meta name="apple-itunes-app" content="app-id={{ site.ios_app_id }}">
 	{% endif %}
 
 	<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.6.3/css/all.css" integrity="sha384-UHRtZLI+pbxtHCWp1t77Bi1L4ZtiqrqD80Kn4Z8NTSRyMA2Fd33n5dQ8lWUE00s/" crossorigin="anonymous">