add sloc(source line of code) static calc

package.json

@@ -18,8 +18,10 @@
     "lint": "npm run eslint && npm run tslint",
     "eslint": "eslint \"{src,test,bin}/**/*.js\"",
     "tslint": "tslint \"{src,test,bin}/**/*.ts\"",
+    "sloc": "sloc . --details --format cli-table --keys total,source,comment --exclude 'node_modules|doc' && sloc . --exclude 'node_modules|doc'",
     "pretest": "npm run lint",
     "test": "npm run test:phantomjs && npm run test:chrome",
+    "posttest": "npm run sloc",
     "test:phantomjs": "cross-env LC_ALL=C WECHATY_LOG=info WECHATY_HEAD=phantomjs ava --timeout=10m \"{src,test}/**/*.spec.js\"",
     "test:chrome": "cross-env LC_ALL=C WECHATY_LOG=silly WECHATY_HEAD=chrome ava --timeout=10m \"{src,test}/**/*.spec.js\"",
     "testdev": "cross-env LC_ALL=C WECHATY_LOG=silly ava --serial --verbose --fail-fast --timeout=3m",
@@ -98,6 +100,7 @@
     "eslint-plugin-ava": "^3.0.0",
     "qrcode-terminal": "^0.10.0",
     "sinon": "^1.17.5",
+    "sloc": "^0.1.11",
     "tslint": "^3.15.1",
     "tuling123-client": "0.0.1",
     "typescript": "^2.1.0-dev.20160830"