Cleanup

[randomComitter]

It's sad that this nice library has a bit outdated structure and styling.
I restructured the files and refactored the code to better comply to psr-2 coding style guide.
Tests and readme were also modified.

[qyanu]

@WallTearer since some of your propsed changes are already included (by some other means): what do you think remains of your cleanup proposals?

[randomComitter]

@qyanu, sorry, I completely missed your question.
I guess this lib looks way nicer now than before, cause it has a better file structure, namespaces, no global constants, so my pull request doesn't bring anything really special. You can discard/close it if you want.