Remove LAUNCHER category from VPN settings activity's intent filter.

Also add preference summary to the VPN entry in the security settings.
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 20f43c9..03978cc 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -115,9 +115,8 @@
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <action android:name="android.net.vpn.SETTINGS" />
-                <action android:name="android.net.vpn.INSTALL_PROFILE" />
-                <category android:name="android.intent.category.LAUNCHER" />
                 <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.VOICE_LAUNCH" />
             </intent-filter>
         </activity>