consume v0.15 of @lukka scoped packages

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "libs"]
-	path = libs
-	url = https://github.com/lukka/run-cmake-vcpkg-action-libs.git

README.md

@@ -108,6 +108,16 @@ Features available only in the GitHub version of **'run-cmake'**:
 ## Prerequisites
 [gulp 4](https://www.npmjs.com/package/gulp4) globally installed.
 
+### Setup for GitHub Registry public packages
+
+`run-vcpkg` depends on public NPM packages published by [lukka/run-cmake-vcpkg-action-libs](https://github.com/lukka/run-cmake-vcpkg-action-libs) in the [GitHub Packages registry](https://docs.github.com/en/free-pro-team@latest/packages/using-github-packages-with-your-projects-ecosystem/configuring-npm-for-use-with-github-packages).
+Unexpectedly, a public package still requires authentication when downloading it, hence if you want to `npm install` those packages correctly, you need to obtain a token with `read:packages` scope. Then create in the root of the repository a `.npmrc` file with the following content:
+
+   //npm.pkg.github.com/:_authToken=YOURTOKEN
+   @lukka:registry=https://npm.pkg.github.com/
+
+__Note__: **Never commit this `.npmrc` file!**
+
 ## Build and lint
 Build with `tsc` running: