Fix for output filter not preserving spaces.

The filter was using bare 'read' which was not working with the
leading spaces. Must use -r and clear IFS for this to work.

common

@@ -259,7 +259,7 @@ function output_filter() {
         indent='    '
     fi
 
-    while read line ; do
+    while IFS= read -r line ; do
         if [[ "$nlines" == '0' ]] ; then
             if [[ "$start" != '' && "$start" != '+' ]] ; then
               echo "  $start"