Update license link in readme

update-license-link.js

var fs = require('fs');
var path = require('path');
var readFile = promisify(fs.readFile);
var writeFile = promisify(fs.writeFile);

module.exports = {
	getOptions: function () {
		return [];
	},
	
	run: function (directory, opts) {
		var licensePromise = getMDFileByName(directory, 'license');
		var readmePromise = getMDFileByName(directory, 'readme');
		var readFileName;
		return Promise.all([
			licensePromise,
			readmePromise
		]).then(([licenseFileName, readmeFileName]) => {
			if(!licenseFileName || !readmeFileName){
				console.error('Skipping...');
				return Promise.resolve();
			}
			return Promise.all([
				licenseFileName,
				readmeFileName,
				readFile(readmeFileName, 'utf8')
			]);
		}).then(([licenseFileName, readmeFileName, readmefile]) => {
			return Promise.all([
				readmeFileName,
				readmefile.replace('LICENSE.md', path.parse(licenseFileName).name)
			]);
		}).then(([readmeFileName, readmefile]) => {
			return writeFile(readmeFileName, readmefile);
		});
	}
};

function getMDFileByName(directory, name){
	return new Promise((resolve, reject) => {
		fs.readdir(directory, (err, files) => {
			if(err) return reject(err);
			var fileName = files.find(item => {
				item = item.toLowerCase();
				return item.startsWith(name) && (item.endsWith('md') || item.endsWith('markdown')) || item === name;
			});
			resolve(fileName ? path.join(directory, fileName) : null);
		});
	});
}

function promisify(fn){
	return function(){
		return new Promise((resolve, reject) => {
			fn.apply(fn, [...arguments, (err, result) => {
				if(err){
					return reject(err);
				}
				resolve(result);
			}]);
		});
	};
}