Fix main and types paths

These paths should refer to the files as they end up in the NPM package. For more information, please see #20.

Signed-off-by: Arend van Beelen jr <arend@arendjr.nl>

package.json

@@ -8,8 +8,8 @@
     "watch": "tsc -p ./src --watch",
     "test": "mocha"
   },
-  "main": "lib/index.js",
-  "types": "lib/index.d.ts",
+  "main": "index.js",
+  "types": "index.d.ts",
   "license": "MIT",
   "repository": {
     "type": "git",