strict: Made strict mode explicit

lib/assert.js

@@ -1,3 +1,5 @@
+'use strict';
+
 const assert = require('assert');
 const util = require('util');
 const fail = assert.fail;

package.json

@@ -4,7 +4,7 @@
   "description": "Core assert library extended slightly with few more assertion methods",
   "main": "lib/assert.js",
   "scripts": {
-    "test": "env NODE_ENV=test mocha --recursive --use_strict"
+    "test": "env NODE_ENV=test mocha --recursive"
   },
   "repository": {
     "type": "git",

test/assert.test.js

@@ -1,3 +1,5 @@
+'use strict';
+
 const assert = require('assert');
 const util = require('util');
 const assertExtended = require('../lib/assert');