codestyle fix

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #5
| License       | MIT

I added doc-blocks, removed unused imports, empty lines, added file headers etc.
@WouterJ, @rande have a look and see if we all agree about the standards.

Pretty sure I still need to update this a couple of times still so don't merge yet please.