contributors.sh: --releasenotes reads in names from RELEASE-NOTES

This is very handy when updating the RELEASE-NOTES as then we sometimes
have names added manually in the existing list and we use this script to
update the set.

contributors.sh

@@ -25,6 +25,10 @@
 # This script shows all mentioned contributors from <hash> until HEAD. To aid
 # when writing RELEASE-NOTES and THANKS.
 #
+# Use --releasenotes to also include the names from the existing RELEASE-NOTES
+# file, which is handy when we've added names manually in there that should be
+# included in an updated list.
+#
 
 start=$1
 
@@ -41,13 +45,25 @@ fi
 # only count names with a space (ie more than one word)
 # sort all unique names
 # awk them into RELEASE-NOTES format
+(
 git log $start..HEAD | \
 egrep -i '(Author|Commit|by):' | \
 cut -d: -f2- | \
 cut '-d<' -f1 | \
 tr , '\012' | \
 sed 's/ and /\n/' | \
-sed -e 's/^ //' -e 's/ $//g' | \
+sed -e 's/^ //' -e 's/ $//g'
+
+if echo "$*" | grep -qw -- '--releasenotes';then
+    # if --releasenotes was used
+    # grep out the list of names from RELEASE-NOTES
+    # split on ", "
+    # remove leading white spaces
+grep "^  [^ ]" RELEASE-NOTES| \
+sed 's/, */\n/g'| \
+sed 's/^ *//'
+fi
+)| \
 sed -f ./docs/THANKS-filter | \
 grep ' ' | \
 sort -fu | \