Add lerna-changelog dev dependency

Author: Turbo87

package.json

@@ -18,6 +18,7 @@
     "url": "git+https://github.com/ember-cli/broccoli-uglify-sourcemap.git"
   },
   "scripts": {
+    "changelog": "lerna-changelog",
     "test": "jest",
     "test:coverage": "jest --coverage",
     "test:watch": "jest --watchAll"
@@ -41,7 +42,8 @@
     "broccoli-test-helper": "^1.2.0",
     "eslint-plugin-node": "^6.0.1",
     "jest": "^21.2.1",
-    "jest-runner-eslint": "^0.5.0"
+    "jest-runner-eslint": "^0.5.0",
+    "lerna-changelog": "^0.7.0"
   },
   "changelog": {
     "repo": "ember-cli/broccoli-uglify-sourcemap",