Added check for carriage return (#9065)

Change-Id: I5ab56fb58fb7db2542678845bddf6a7e971fd6ca

checkstyle/vaadin-checkstyle.xml

@@ -60,7 +60,11 @@
 	<module name="NewlineAtEndOfFile">
 		<property name="severity" value="warning" />
 	</module>
-
+	<module name="RegexpMultiline">
+		<property name="message" value="File contains carriage return (Windows newlines)" />
+		<property name="format" value="\r"/>
+	</module>
+    
 
 	<!-- Checks that property files contain the same keys. -->
 	<!-- See http://checkstyle.sf.net/config_misc.html#Translation -->