Update go.md

Hi Georgi,

I love this article. I wish people would write more articles like this one to give insight into Go's data structures and memory allocations. The only similar one I've seen so far is [Russ Cox's article](http://research.swtch.com/godata). I have some suggestions that I think would make the article more understandable with regards to the differences between the data structures in the examples.

Feel free to dismiss the PR if you don't like (agree with) them.

G