go.blog: add html2article tool
go.blog: add html2article tool

R=nigeltao
CC=golang-dev
https://codereview.appspot.com/10224043

d0f/go-zh.blog,webfd/go-zh.blog,bryanxu/go-zh.blog,webfd/go-zh.blog,d0f/go-zh.blog,bryanxu/go-zh.blog