macOS: use HTTPS for appcast (#325)

client/Info.plist

@@ -9,7 +9,7 @@
 	<key>CFBundleIdentifier</key>
 	<string>com.vcmi.vcmiclient</string>
 	<key>SUFeedURL</key>
-	<string>http://vcmi.eu/sparkle_appcast.xml</string>
+	<string>https://vcmi.eu/sparkle_appcast.xml</string>
 	<key>SUPublicDSAKeyFile</key>
 	<string>vcmi_dsa_public.pem</string>
 </dict>

osx/sparkle_appcast.xml

@@ -2,9 +2,9 @@
 <rss version="2.0" xmlns:sparkle="http://vcmi.eu/xml-namespaces/sparkle"  xmlns:dc="http://purl.org/dc/elements/1.1/">
    <channel>
       <title>VCMI App Changelog</title>
-      <link>http://vcmi.eu/sparkle_appcast.xml</link>
+      <link>https://vcmi.eu/sparkle_appcast.xml</link>
       <description>Most recent changes with links to updates.</description>
-      <language>en</language>      
+      <language>en</language>
          <item>
             <title>Version 0.94</title>
             <description>Version 0.94</description>
@@ -27,4 +27,4 @@
             <enclosure url="http://download.vcmi.eu/vcmi-0.92.dmg" sparkle:version="0.92" length="34906250" type="application/octet-stream" sparkle:dsaSignature="MC0CFF75UKfXunY2GNSW4hs1O6MaWycLAhUA3YiRM9uUrnoS/PhWHgjRjwWcHo4=" />
          </item>
    </channel>
-</rss>
+</rss>