Merge pull request rms-open-letter#2154 from kevinr/patch-1

add signature

Author: neilmcgovern

index.md

@@ -1422,6 +1422,7 @@ identification purposes only and does not constitute endorsement.)</small>
 1. Kevin Messer
 1. Kevin O'Brien
 1. Kevin P. Fleming
+1. Kevin Riggle
 1. Kevin Sonney
 1. Kev Quirk
 1. Khionu Sybiern