Hotfix/versions exports (#35)

* Strict versions.

* Exports and versions.

* Updated plugins.

* Added missing types.

* Updates.

Author: Eimantas Dumšė

examples/webpack-builder-plugin-example/package-lock.json

@@ -5,10 +5,11 @@
         "build": "lerna run build",
         "test": "lerna run test",
         "bootstrap": "lerna bootstrap",
-        "pack": "lerna exec -- npm pack"
+        "pack": "lerna exec -- npm pack",
+        "clean": "lerna clean"
     },
     "devDependencies": {
-        "lerna": "3.16.4",
+        "lerna": "3.19.0",
         "npm-run-all": "4.1.5"
     }
 }