Fixes less#3434 - memory / runtime improvements (less#3572)

* Remove class extends pattern for nodes
* Fix node benchmark
* v3.13.0
* Restore tree caching

Author: matthew-dean

dist/less.js

@@ -3,5 +3,5 @@
     "packages/*"
   ],
   "npmClient": "npm",
-  "version": "3.12.2"
+  "version": "3.13.0"
 }

dist/less.min.js

@@ -1,7 +1,7 @@
 {
   "name": "@less/root",
   "private": true,
-  "version": "3.12.2",
+  "version": "3.13.0",
   "description": "Less monorepo",
   "homepage": "http://lesscss.org",
   "scripts": {

dist/less.min.js.map

@@ -243,9 +243,6 @@ module.exports = function(grunt) {
             benchmark: {
                 command: "node benchmark/index.js"
             },
-            benchmarkbrowser: {
-                command: "node test/browser/generator/runner.js benchmark"
-            },
             opts: {
                 // test running with all current options (using `opts` since `options` means something already)
                 command: [
@@ -416,15 +413,8 @@ module.exports = function(grunt) {
     ]);
 
     // Run benchmark
-    grunt.registerTask("benchmark-node", [
+    grunt.registerTask("benchmark", [
         "shell:testcjs",
         "shell:benchmark"
     ]);
-
-    // Run all browser tests
-    grunt.registerTask("benchmark", [
-        "browsertest-lessjs",
-        "connect",
-        "shell:benchmarkbrowser"
-    ]);
 };