added packer and build script

tools/janken/.gitignore

@@ -10,6 +10,7 @@
 
 # production
 /build
+/tool
 
 # misc
 .DS_Store

tools/janken/package.json

@@ -2,6 +2,7 @@
   "name": "catherine-janken",
   "version": "0.1.0",
   "private": true,
+  "homepage": "tool",
   "dependencies": {
     "dotenv": "^8.2.0",
     "node-sass": "^4.13.1",
@@ -28,7 +29,7 @@
   },
   "scripts": {
     "start": "react-scripts start",
-    "build": "react-scripts build",
+    "build": "react-scripts build && rm -rf tool && mv build tool",
     "test": "react-scripts test",
     "eject": "react-scripts eject"
   },