typo fixed

Author: fvarrui

src/main/java/io/github/fvarrui/javapackager/packagers/GenerateMsi.java

@@ -50,7 +50,7 @@ protected File doApply(WindowsPackager packager) throws Exception {
 		VelocityUtils.render("windows/wxs.vtl", wxsFile, packager);
 		Logger.info("WXS file generated in " + wxsFile + "!");
 
-		// pretiffy wxs
+		// prettify wxs
 		XMLUtils.prettify(wxsFile);
 
 		// candle wxs file