Cleaner markdownified readme

Experimental: Readme Cleanup Example
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@mhord - here's a sample branch to demonstrate the type of README cleanup I'd like to do across several other of SparkFun's public branches. Changes:

* Ported from a text file to a *.md file
* Added product image, sku, and name that link to the product on sparkfun.com
* Put headers on the three main sections (two license sections and version history - I opted not to put a header up top as the image serves as an excellent header itself)
* Linked to license info where applicable

No README content has changed.

Do these changes seem about right? Helpful or nuisance? Also, is pushing a branch directly to the repo and issuing a pull req from there (as opposed to form a fork) a good way to go about it?