add check for line endings containing CR.

.github/checks/lineendings.sh

@@ -0,0 +1,18 @@
+#! /bin/bash
+OLDCWD=`pwd`
+SCRIPT_PATH=`dirname $0`
+CHECK_PATH=.
+
+cd $SCRIPT_PATH/../../
+
+FILES=`find $CHECK_PATH -type f \( -name \*.inc -o -name Makefile -o -name \*.cfg -o -name \*.\[chs\] -o -name \*.mac -o -name \*.asm -o -name \*.sgml \) -print | grep -v "libwrk/" | grep -v "testwrk/" | xargs grep -IUl $'\r'`
+
+cd $OLDCWD
+
+if [ x"$FILES"x != xx ]; then
+    echo "error: found CR in the following files:" >&2
+    for n in $FILES; do
+        echo $n >&2
+    done
+    exit -1
+fi