Add clean script

package.json

@@ -24,6 +24,7 @@
     "pretest": "./node_modules/.bin/eslint *.js test",
     "test": "node scripts/test",
     "start": "node ./scripts/start",
+    "clean": "node ./scripts/clean",
     "test-e2e-ios": "node ./scripts/test-e2e --ios",
     "test-e2e-ios-release": "node ./scripts/test-e2e --ios --release",
     "test-unit-ios": "node ./scripts/test-unit --ios",

scripts/clean.js

+const exec = require('shell-utils').exec;
+
+run();
+
+function run() {
+  exec.killPort(8081);
+  exec.execSync(`watchman watch-del-all || true`);
+  exec.execSync(`adb reverse tcp:8081 tcp:8081 || true`);
+  exec.execSync(`rm -rf lib/ios/DerivedData`);
+  exec.execSync(`rm -rf example/ios/DerivedData`);
+  exec.execSync(`rm -rf lib/android/build`);
+  exec.execSync(`rm -rf lib/android/app/build`);
+  exec.execSync(`rm -rf example/android/build`);
+  exec.execSync(`rm -rf example/android/app/build`);
+  exec.execSync(`rm -rf lib/dist`);
+}