Fixed release build numbering

Jenkinsfile

@@ -25,7 +25,9 @@ pipeline {
 
           env.DEPLOY_BUILD = 'false'
 
-          def releaseMatch = branch =~ /^release\/(\d+\.\d+\.\d+)$/
+          // A release branch supplies major.minor; Jenkins supplies the patch
+          // number so release/2.0 build 1 becomes 2.0.1-RELEASE.
+          def releaseMatch = branch =~ /^release\/(\d+\.\d+)$/
           if (releaseMatch.matches()) {
             env.BUILD_VERSION = "${releaseMatch[0][1]}.${env.BUILD_NUMBER}-RELEASE"
             env.DEPLOY_BUILD = 'true'