Updating icon of NuGet package for 2.0.x-pre

Author: gsscoder

art/CommandLine20.png

@@ -11,7 +11,7 @@
         <licenseUrl>https://raw.github.com/gsscoder/commandline/master/doc/LICENSE</licenseUrl>
         <projectUrl>https://github.com/gsscoder/commandline</projectUrl>
         <owners>Giacomo Stelluti Scala</owners>
-        <iconUrl>https://github.com/gsscoder/commandline/raw/master/art/CommandLine.png</iconUrl>
+        <iconUrl>https://github.com/gsscoder/commandline/raw/master/art/CommandLine20.png</iconUrl>
         <requireLicenseAcceptance>false</requireLicenseAcceptance>
         <tags>command line argument option parser parsing library syntax shell</tags>
     </metadata>
@@ -22,4 +22,4 @@
         <file src='..\build\CommandLine.XML' target='lib\net45\CommandLine.XML'/>
         <file src='.\readme.txt' target='readme.txt'/>
     </files>
-</package>
+</package>