Go over the code of current versions of `autoindex` pick mergeable changes
As shown by issue #37, the module should be doing some things a bit differently. It would be a good thing to look at autoindex built-in module and see which changes would be worth integrating. After all, fancyindex used from the beginning the code of autoindex as a starting point, and surely it has changed along with Nginx.
It is surprising (in a good way) that fancyindex didn't need many modifications to keep working as new Nginx releases were posted. This tells many good things about Nginx as a project. But also let's not forget that I started the fancyindex module in 2007 (almost a decade ago!), and it would be indeed very good to properly check what happened to autoindex in the meanwhile.
Pushed to milestone v0.5.0, because the upstream code for autoindex has now a few new features (e.g. returning directory listings as JSON).