Merge pull request rms-open-letter#1394 from briancurtin/patch-1

Add Brian Curtin signature

Author: neilmcgovern

index.md

@@ -255,6 +255,7 @@ identification purposes only and does not constitute endorsement.)</small>
 1. Brett Sheffield (Librecast Project)
 1. Brett Smith (Former FSF staff and member)
 1. Brian Chen (`betaveros`)
+1. Brian Curtin (Fellow at Python Software Foundation, former board member)
 1. Brian Dawn
 1. Brian Heim
 1. Brian Ketelsen