Fixed some Heap stuff and a typo

Thanks much for putting this sheet together.

I have a couple of patches to propose. One patch fixes the description of the Binomial Heap to be more comparable with the Fibonacci Heap description, and also marks the Heaps as Max Heaps so their operations make clear sense. The other patch fixes a typo.

You might consider checking some CSS and other infrastructure into the repo so that people can check their work locally before issuing pull requests. I've got something if you want it. The biggest problem is how to properly track the Bootstrap CSS.