fix: package.json for module

package.json

@@ -2,13 +2,15 @@
   "name": "ml-matrix-peaks-finder",
   "version": "0.3.0",
   "description": "The peak picking routines for 2D arrays. This library looks for the local maxima of the given input matrix. The input matrix has to be specified as a single vector.",
-  "main": "./src/index.js",
+  "main": "lib/index.js",
+  "module": "src/index.js",
   "files": [
     "src"
   ],
   "scripts": {
     "eslint": "eslint src",
     "eslint-fix": "npm run eslint -- --fix",
+    "prepublishOnly": "rollup -c",
     "build": "cheminfo build --root matrix-peaks-finder --no-uglify",
     "test": "npm run test-coverage && npm run eslint",
     "test-coverage": "jest --coverage",