[Feature request] a better README.md

[zetok]

• how to build
• should clearly state that it's dual-licensed, just putting both licenses in repo isn't really meaningful
• does it even compile on stable?

[zeyonaut]

In addition to that, stating the requirements for contributing both legal and other, and some screenshots/example code to get new users started.

[snuk182]

• is it ever possible to build it on Windows, both with GNU & MSVC.
  UPD possible, but with adventures.

[faraazahmad]

Is this project still active?

[mitchhentges]

No, but one of the strongest forks is leotindall's