feat: custom include paths and esbuild jest config

[mariobm]

Added new feature:

• option: includePaths for including external directories in loader (i needed this feature so i decided to add it)
• esbuild for jest config

// craco.config.js
const CracoEsbuildPlugin = require("craco-esbuild");

module.exports = {
  plugins: [
    {
      plugin: CracoEsbuildPlugin,
      options: {
        esbuildLoaderOptions: {
          includePaths: ["/some/external/dir"], // includePaths is optional
          loader: "jsx",
          target: "es2015",
        },
      },
    },
  ],
};

Closes #2

[mariobm]

Hi just added support for external dir and managed to get working overrideJestConfig.
The code is commented.

[pradel]

Wow super cool that you got the jest config working, thanks for this 🚀
I left some small comments and I can release a new version once resolved!

[pradel]

@mariobm the tests are failing looks like there is something wrong in the logic