provide doxygen reference documentation

[lammermann]

I've seen you've got a doxyfile but I can't find the generated docs anywhere on the web. The links in doc/README.md redirect to a not existing adress.
Could you put the developer reference in some proper place?
An easy solution would be to use github-pages and intergrate it in the automatic build process with git hooks.

[warrenseine]

The link is the README refers to an old version of Minko that is not maintained, so we simply disabled the site to avoid confusion.

I'll think about automating the developer reference generation. Maybe I could teach Travis to do that.

Thanks!