Compile also as ES6 modules for better tree-shaking

[StefanoMagrassi]

TS sources has to be compiled also as ES6 module into a specific directory and the path has to be set in the package.json's module field.

Furthermore, the package.json's sideEffects field has to be set to false.

This will help tools like Webpack or Rollup to better apply "tree-shaking" when blundling projects which use appy.

package.json:

{
  ...
  "module": "lib/es6/index.js",
  "sideEffects": false,
  ...
}

tsconfig-compile-es6.json:

{
  "extends": "./tsconfig-compile",
  "compilerOptions": {
    "target": "es6",
    "module": "es6"
  }
}

---

refs:

• https://webpack.js.org/guides/tree-shaking/
• https://survivejs.com/webpack/optimizing/tree-shaking/#tree-shaking-on-package-level

[StefanoMagrassi]

closed by #111