Add namespaces

[jenstornell]

I would like to contribute to the project, as soon as I saw it I liked it, I was looking for a simple way to compress the html code and I found this. I have knowledge of composer, I agree with @Modicrumb, you have to use namespaces. I could do a pull-request with this change.

Originally posted by @EdixonAlberto in #17 (comment)

[jenstornell]

@EdixonAlberto You can contribute with pull request if you like. Small pull requests have a better chance at being merged faster. Thanks!

[EdixonAlberto]

I'm going to make an important contribution to the library to use in the future namespace. But before they should make the following changes:

• apply good practices, using PSRs
• upload the library to composer, fulfilling the following requirements
• use the PSR-4 class autoloader