Add docker image

Dockerfile

@@ -0,0 +1,5 @@
+FROM node:8-alpine
+
+RUN npm i -g fx
+
+ENTRYPOINT ["fx"]

package.json

@@ -21,7 +21,12 @@
     "test": "ava",
     "build": "pkg . --out-path dist -t node8-linux-x64,node8-macos-x64,node8-win-x64",
     "zip": "cd dist && find . -name 'fx-*' -exec zip '{}.zip' '{}' \\;",
-    "release": "rm -rf ./dist && npm run build && npm run zip && release-it --github.release --github.assets=dist/*.zip"
+    "release": "rm -rf ./dist && npm run build && npm run zip && release-it --github.release --github.assets=dist/*.zip",
+    "brew:release": "brew bump-formula-pr --url=https://registry.npmjs.org/fx/-/fx-`fx package.json .version`.tgz --no-audit fx",
+    "docker:build": "docker build -t antonmedv/fx:latest .",
+    "docker:tag": "docker tag antonmedv/fx:latest antonmedv/fx:`fx package.json .version`",
+    "docker:push": "docker push antonmedv/fx:latest && docker push antonmedv/fx:`fx package.json .version`",
+    "docker:release": "npm run docker:build && npm run docker:tag && npm run docker:push"
   },
   "keywords": [
     "json",