Fix typo in RemotingServer App.Config

Config file had sppendToFile element name instead of appendToFile.

Author: craigdfrench

examples/net/2.0/Remoting/RemotingServer/cs/src/App.config

@@ -34,7 +34,7 @@
 		</appender>
 		<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
 			<file value="log-file.txt" />
-			<sppendToFile value="true" />
+			<appendToFile value="true" />
 			<layout type="log4net.Layout.PatternLayout">
 				<header value="FILE HEADER&#13;&#10;" />
 				<footer value="FILE FOOTER&#13;&#10;" />