update: use vue-demi again to add compatability to vue2

* add vite.config.app.ts for demo generation

package.json

@@ -8,7 +8,8 @@
   },
   "license": "MIT",
   "author": "Burak Cakmakoglu",
-  "main": "dist/revue-flow.es.js",
+  "main": "dist/index.js",
+  "module": "dist/revue-flow.es.js",
   "types": "dist/index.d.ts",
   "files": [
     "dist",
@@ -18,6 +19,7 @@
     "dev": "vite",
     "build": "vue-tsc --noEmit && vite build && yarn build:dist",
     "build:dist": "rollup -c --environment NODE_ENV:production",
+    "build:app": "vite build -c vite.config.app.ts",
     "serve": "vite preview",
     "prepublishOnly": "yarn build",
     "test": "exit 0;",
@@ -31,7 +33,7 @@
     "d3-zoom": "^3.0.0",
     "fast-deep-equal": "^3.1.3",
     "pinia": "^2.0.0-beta.3",
-    "vue": "^3.0.5"
+    "vue-demi": "latest"
   },
   "devDependencies": {
     "@babel/core": "^7.14.6",
@@ -67,7 +69,12 @@
     "rollup-plugin-typescript2": "^0.30.0",
     "typescript": "^4.3.5",
     "vite": "^2.3.8",
-    "vue-tsc": "^0.0.24"
+    "vue-tsc": "^0.0.24",
+    "vue": "^3.0.5"
+  },
+  "peerDependencies": {
+    "@vue/composition-api": "^1.0.0-rc.13",
+    "vue": "^2.6.0 || >=3.0.5"
   },
   "publishConfig": {
     "access": "public",