added VersionSelectorScript.groovy to select builders for Node version

jenkins/scripts/VersionSelectorScript.groovy

@@ -0,0 +1,61 @@
+def canBuild(nodeMajorVersion, builderLabel) {
+
+  // Linux
+  if (builderLabel.indexOf('centos5') == 0 && nodeMajorVersion >= 8)
+    return false
+  if (builderLabel.indexOf('centos6') == 0 && nodeMajorVersion < 8)
+    return false
+
+  // Windows
+  if (builderLabel.indexOf('vs2013-') == 0 && nodeMajorVersion >= 6)
+    return false
+  if (builderLabel.indexOf('vs2015-') == 0 && (nodeMajorVersion < 6 || nodeMajorVersion >= 10))
+    return false
+  if (builderLabel.indexOf('vs2017-') == 0 && nodeMajorVersion < 10)
+    return false
+
+  // SmartOS
+  if (builderLabel.indexOf('smartos13') == 0) // Node.js 0.x
+    return false
+  if (builderLabel.indexOf('smartos14') == 0 && nodeMajorVersion >= 8)
+    return false
+  if (builderLabel.indexOf('smartos15') == 0 && nodeMajorVersion < 8)
+    return false
+
+
+  // PPC BE
+  if (builderLabel.indexOf('ppcbe-ubuntu') == 0 && nodeMajorVersion >= 8)
+    return false
+
+  // s390x
+  if (builderLabel.indexOf('s390x') > -1 && nodeMajorVersion < 6)
+    return false
+
+  // AIX61
+  if (builderLabel.indexOf('aix61') > -1 && nodeMajorVersion < 6)
+    return false
+
+  return true
+}
+
+// setup for execution of the above rules
+
+int nodeMajorVersion = -1
+if (parameters['NODEJS_MAJOR_VERSION'])
+  nodeMajorVersion = parameters['NODEJS_MAJOR_VERSION'].toString().toInteger()
+println 'Node.js major version: ' + nodeMajorVersion
+println 'Node.js version: ' + parameters['NODEJS_VERSION']
+
+result['nodes'] = []
+
+combinations.each{
+  def builderLabel = it.nodes
+  if (nodeMajorVersion >= 4) {
+    if (!canBuild(nodeMajorVersion, builderLabel)) {
+      println 'Skipping ' + builderLabel + ' for Node.js ' + nodeMajorVersion
+      return
+    }
+  }
+  result['nodes'] << it
+}
+