Update appcast.xml

Author: sbarex

appcast.xml

@@ -2,10 +2,33 @@
 <rss xmlns:sparkle="http://www.andymatuschak.org/xml-namespaces/sparkle" version="2.0">
     <channel>
         <title>Syntax Highlight</title> 
+        <item>
+            <title>2.1.8</title>
+            <pubDate>sab, 12 feb 2022 12:18:00 +0100</pubDate>
+            <sparkle:minimumSystemVersion>10.15</sparkle:minimumSystemVersion>
+            <enclosure type="application/octet-stream" url="https://github.com/sbarex/SourceCodeSyntaxHighlight/releases/download/2.1.8/Syntax.Highlight.zip" sparkle:shortVersionString="2.1.8" sparkle:version="55" sparkle:edSignature="Z+MQ2qtLIMolkVIgHtqY687mdjXhlecLyiL+jT6iNgTgk2dLNRVOPrmxRQ6si/g8v/52cSkdeHPx1zubokY0Ag==" length="12526094" />
+            <description><![CDATA[
+                <h2>Release 2.1.8 (55)</h2>
+                <p>New features:</p>
+                <ul>
+                    <li>Better support Gdscript files (Godot engine) (<code>.gd</code>).</li>
+                    <li>Highlight updated to version 4.2.</li>
+                </ul>
+                <p><b>In release 2.1.6 the automatic update does not work and you have to <a href="https://github.com/sbarex/SourceCodeSyntaxHighlight/releases/download/2.1.8/Syntax.Highlight.zip">manually download the application from the web</a>.</b></p>
+                <ol>
+                    <li>Unzip the archive</li>
+                    <li>Replace the app inside the <code>Applications</code> folder</li>
+                    <li>Start <code>Syntax Highlight</code> with right click (or cmd-click) and choose open from the context menu.</li>
+                </ol>
+
+                <p><a href="https://github.com/sbarex/SourceCodeSyntaxHighlight/blob/master/CHANGELOG.md">See the complete changelog.</a></p>
+            ]]>
+            </description>
+        </item>
 
         <item>
             <title>2.1.7</title>
-            <pubDate>ven, 18 feb 2021 18:35:00 +0100</pubDate>
+            <pubDate>ven, 11 feb 2022 18:35:00 +0100</pubDate>
             <sparkle:minimumSystemVersion>10.15</sparkle:minimumSystemVersion>
             <enclosure type="application/octet-stream" url="https://github.com/sbarex/SourceCodeSyntaxHighlight/releases/download/2.1.7/Syntax.Highlight.zip" sparkle:shortVersionString="2.1.7" sparkle:version="54" sparkle:edSignature="KjgtrLI7DRq3VeG4AhMEw+wIOZK+xyZ62xCWSrpm1XrcJqDkE/UtQ/kHbHcJjWdjtzA5Y4hzb2thHQELcVADCQ==" length="11412497" />
             <description><![CDATA[