User JSX and update package.json to install react@0.12.0-rc1 and reactify for 0.12

It looks like 0.12 didn't publish yet and only 0.12.0-rc1 is available.
reactify didn't publish the newest one yet and after my testing, 0.15-dev is workable but you need to install it via github repo.
In my machine, npm install works fine for me.

I also remove createFactory since we will use JSX and compiler will help us to handle this.
Please feel free to merge or change it :)