Project folder structure

Can I suggest to change project structure to this?
 ```
patterns/
   behavioral
      ...
   creational
      ...
   structural
      ...
   ...
tests/
   behavioral
      ...
   creational
      ...
   structural
      ...
setup.cfg
.travis.yml
...
```
It is more common among python packages.
It would be possible to run commands like `pytest patterns` or `flake8 patterns`