Switch to rimraf for cleanup.

package-lock.json

@@ -10416,6 +10416,12 @@
         }
       }
     },
+    "preact": {
+      "version": "8.2.4",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-8.2.4.tgz",
+      "integrity": "sha1-FE6lDLV7dlmsX2MRkblBi97H7Qo=",
+      "dev": true
+    },
     "preact-compat": {
       "version": "3.17.0",
       "resolved": "https://registry.npmjs.org/preact-compat/-/preact-compat-3.17.0.tgz",

package.json

@@ -8,7 +8,7 @@
     "build": "webpack",
     "build:production": "npm run -s build -- --env production",
     "build:development": "npm run -s build -- --env development",
-    "clean": "nwb clean-app",
+    "clean": "rimraf build dist",
     "docker-compose": "docker-compose -f docker-compose.local.yml",
     "docker:down:clean": "npm run -s docker:down -- --rmi all -v",
     "docker:down": "npm run -s docker-compose -- down",
@@ -80,6 +80,7 @@
     "react-hot-loader": "^3.0.0-beta.7",
     "react-router": "^4.2.0",
     "resolve-url-loader": "^2.1.0",
+    "rimraf": "^2.6.1",
     "sass-loader": "^6.0.6",
     "slash": "^1.0.0",
     "style-loader": "^0.18.2",