Fix Liip link

README.md

 * [PHP Brew](https://github.com/phpbrew/phpbrew) - A PHP version manager and installer.
 * [PHP Build](https://github.com/php-build/php-build) - Another PHP version installer.
 * [PHP Env](https://github.com/CHH/phpenv) - Another PHP version manager.
-* [PHP OSX](http://php-osx.liip.ch/) - A PHP installer for OSX.
+* [PHP OSX](https://php-osx.liip.ch/) - A PHP installer for OSX.
 * [PHP Switch](https://github.com/jubianchi/phpswitch) - Another version manager.
 * [VirtPHP](http://virtphp.org/) - A tool for creating and managing isolated PHP environments.