English Introduce is Too Bad

[cryptozeny]

https://github.com/sugarchain-project/doc/blob/master/introduce_sugarchain.md

we have to rewrite all of them. except Chinese version by @Rakutens

[AestheticSenpai]

well, we can just focus on the English one first and base the rest on that

[cryptozeny]

ok i will write a new one. i will ask you if i done.