Add a chapter to README for making it work on Windows

I'm on Windows 10 (Home) and use Docker Toolbox with VirtualBox (there is no other solution if you're not on Win10 Pro/Enterprise). I made the setup of this repo work with same small adjustments ad descriebd in the README. To avoid adding code which is not necessary on UNIX systems, I'm just describing shell commands one can execute right away.

Notes:

Add config to fix aio error according to https://github.com/farmOS/farmOS/issues/55#issuecomment-369279502 and https://github.com/docker/for-win/issues/1584#issuecomment-362165683
Precent config to be "word-writable" according to: https://github.com/cytopia/devilbox/issues/212

nanoninja / docker-nginx-php-mysql

Add a chapter to README for making it work on Windows #42