add app.manifest_metadata which can be used to provide <meta-data …> elements to the AndroidManifest.xml file

lib/motion/project/template/android.rb

@@ -245,6 +245,13 @@ EOS
 <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="#{App.config.package}" android:versionCode="1" android:versionName="1.0">
 	<uses-sdk android:minSdkVersion="#{App.config.api_version}"/>
 	<application android:label="#{App.config.name}" android:debuggable="true" #{App.config.icon ? ('android:icon="@drawable/' + App.config.icon + '"') : ''}>
+EOS
+    App.config.manifest_metadata.each do |key, val|
+      android_manifest_txt << <<EOS
+		<meta-data android:name=\"#{key}\" android:value=\"#{val}\"/>
+EOS
+    end
+    android_manifest_txt << <<EOS
         	<activity android:name="#{App.config.main_activity}" android:label="#{App.config.name}">
             		<intent-filter>
                 		<action android:name="android.intent.action.MAIN" />

lib/motion/project/template/android/config.rb

@@ -28,7 +28,8 @@ module Motion; module Project;
     register :android
 
     variable :sdk_path, :ndk_path, :avd_config, :package, :main_activity,
-      :sub_activities, :api_version, :arch, :assets_dirs, :icon
+      :sub_activities, :api_version, :arch, :assets_dirs, :icon,
+      :manifest_metadata
 
     def initialize(project_dir, build_mode)
       super
@@ -37,6 +38,7 @@ module Motion; module Project;
       @sub_activities = []
       @arch = 'armv5te'
       @assets_dirs = [File.join(project_dir, 'assets')]
+      @manifest_metadata = {}
     end
 
     def validate