Refactor to flex

By refactoring to flex we will also be able to append items and change the order (reverse or something), by just appending a class name. We can also use 'order' to make items appear first.

v1.0

Supported browsers: IE11, Chrome, Firefox, Safari, Edge (non-chromium)

Beta release

This is the initial release of Mesh. More features will be added before I release the production ready version.