Babel plugin optimize i18n

Babel plugin that transforms this:

import { __, _x } from '@wordpress/i18n';

__( 'Hello' );
_x( 'World' );

to this:

import { __ as alias__, _x as alias_x } from '@wordpress/i18n';
const __ = alias__;
const _x = alias_x;

__( 'Hello' );
_x( 'World' );

Inspired by babel-plugin-optimize-react that does similar transforms for React imports.

The transform ensures that the __('Hello') syntax remains intact in the output bundle (and even after minification if Terser uses the mangle.reserved option) and can be extracted by WP i18n tools.