Adding attributes rowspan, colspan and shape

Hello Li,

Could you please merge into your tree and publish?

You will see that I've simply added the attributes without comments from MDN. I'm sorry for that.
I stopped spending time with MDN when I realized that several attributes are missing from W3C DTDs.

On the other hand, I've researched a way to pull all definitions from W3C DTDs and automagically generate code which will then contain all tags and all attributes. It's late at night now and I'm falling sleep. I will write a proper email about this subject tomorrow.

Thanks