Autogen doc

Add auto-generated documentation. Note that 91.92 % is undocumented.

Suggestion on documenting each module in lib or other *.rb
here we say what does this *.rb does.
task:, Author:, Date:, Copyright:
I'll manage to develop a website for both betty and its documentation in either in jekyll(this way we can run it on Github server) or in Sinatra(this way i push it on betty.herokuapp.com). What do you think?