Add built in option for less support

[swashata]

Many popular libraries like antd, elemental ui uses less. So we should have it built in. Right now, once can do it like

const webpackConfigWithLess = (config, merge, appDir, isDev) => {
	const configWithLess = {
		module: {
			rules: [
				{
					test: /\.less$/,
					use: [
						isDev
							? 'style-loader'
							: {
									loader: MiniCssExtractPlugin.loader,
									options: {
										sourceMap: true,
									},
							  },
						{
							loader: 'css-loader',
							options: {
								importLoaders: 1,
								sourceMap: true,
							},
						},
						{
							loader: 'postcss-loader',
							options: {
								sourceMap: true,
							},
						},
						{
							loader: 'less-loader',
							options: {
								sourceMap: true,
							},
						},
					],
				},
			],
		},
	};

	return merge(config, configWithLess);
};

Tasks

• Add prompt Does your project require less.
• Add hasLess in project config, defaulting to undefined which would behave as false.
• Add less-loader in project.
• Add less in devDependencies of the user if hasLess.
• Add less-loader if needed.
• Turn on inlineJs of less-loader because antd needs it that way.