Add "types" field to package.json

Author: SchoofsKelvin

package.json

@@ -2,6 +2,7 @@
   "name": "ip-matching",
   "version": "1.1.0",
   "main": "lib/index.js",
+  "types": "lib/index.d.ts",
   "description": "See whether an IPv4 or IPv6 address matches an IP (range) or subnetwork",
   "dependencies": {},
   "devDependencies": {