Code style and repo best-practices

[colinodell]

Would you be opposed to me cleaning up the code style to be PSR-2 compliant (so that it passes StyleCI checks)?

I'd also like to perform some minor housekeeping like:

• Using consistent indentation in composer.json (spaces instead of tabs)
• Adding a branch alias for dev-master (like I do here for league/commonmark)
• Adding a LICENSE file to the repo root
• Adding a CHANGELOG and populating it for you

Stuff like that.

I just don't want to start on this work if you're not interested :)

[develpr]

I would love it, and be super super appreciative!

[colinodell]

Awesome! I'll start on that sometime this week (or perhaps even tonight on the off chance my two latest PRs get merged 😉)