Make wiki page

[Cj-bc]

For now, README.md is the only reference of this framework(except source codes themselve.)
I wonder if we gather all knowledges and make a wiki for tutorial, reference, etc.
I've spent so much time to read code in order to understand the framework.
It's really good experience for me and I enjoy reading, but some people doesn't like it.
(and also, I want reference while making my project)

I'm sure it's not a good time to start because #45 (the RFC for 3.0) is on the way.
But I think it'll take long time to release 3.0 so that it's better to have wiki of version 2.0

(I can add Japanese references)