osx: Implement auto-upgrade function using Sparkle

During the upgrade, NFD and ndn-autoupdate will be stopped (and, if
enabled, automatically started with new versions).

Change-Id: I010ae4a8aa6f99a0039d58065ab7eb0c9189a979
diff --git a/ndn-control-center.xml b/ndn-control-center.xml
new file mode 100644
index 0000000..360e599
--- /dev/null
+++ b/ndn-control-center.xml
@@ -0,0 +1,22 @@
+<rss xmlns:sparkle="http://www.andymatuschak.org/xml-namespaces/sparkle" xmlns:dc="http://purl.org/dc/elements/1.1/" version="2.0">
+  <channel>
+    <title>NDN App Changleog</title>
+    <link>
+      https://irl.cs.ucla.edu/~cawka/ndn-control-center.xml
+    </link>
+    <description>Most recent changes with links to updates.</description>
+    <language>en</language>
+    <item>
+      <title>Version 0.1.1 (based on NFD version 0.5.1)</title>
+      <description><![CDATA[
+      ]]>
+      </description>
+      <pubDate>Wed, 1 Feb 2017 20:05:00 +0000</pubDate>
+      <enclosure url="https://irl.cs.ucla.edu/~cawka/NDN-0.1.1.dmg"
+                 sparkle:version="0.1.1"
+                 sparkle:dsaSignature="MC0CFB9uEpOR2T0SNQK5tMdztcUAmq+8AhUAroo1gpugccjxwepKEp+VdgILeNc="
+                 length="30468966"
+                 type="application/octet-stream" />
+    </item>
+  </channel>
+</rss>