Add License in core es6

Tools/Config/config.json

@@ -142,7 +142,8 @@
             },
             "es6": {
                 "packageName": "@babylonjs/core",
-                "readme": "readme-es6.md"
+                "readme": "readme-es6.md",
+                "license": "license.md"
             }
         }
     },

Tools/Publisher/tasks/processEs6Packages.js

@@ -51,6 +51,13 @@ function processEs6Packages(version) {
             fs.copySync(source, destination);
         }
 
+        if (es6Config.license) {
+            let source = path.join(config.computed.rootFolder, es6Config.readme);
+            let destination = path.join(packagePath, "license.md");
+            colorConsole.log("    Copy es6 license file: ", source.cyan, destination.cyan);
+            fs.copySync(source, destination);
+        }
+
         umdPackageJson.name = es6Config.packageName;
         umdPackageJson.version = version;
         umdPackageJson.main = es6Config.index || "index.js";
@@ -68,6 +75,10 @@ function processEs6Packages(version) {
             umdPackageJson.files = files;
         }
 
+        if (es6Config.license && umdPackageJson.files.indexOf("license.md") === -1) {
+            umdPackageJson.files.push("license.md");
+        }
+
         ["dependencies", "peerDependencies", "devDependencies"].forEach(key => {
             if (umdPackageJson[key]) {
                 let dependencies = umdPackageJson[key];