Adding a README.md

Hi There.

I noticed the thread in SF where you mention this repository you are maintaining. As I wanted to try and work on a patch for KeePass I forked your repo and immediately noticed the lack of a README.md file. 

I will understand if you chose not to accept this file as it "stains" the purity of the original repo. But I tried to flag it as much as I could as "non-belonging" (and I assumed it would be the only file in that situation). 

Regards,
Carlos.