* Fixed typos and broken links
The link to hardware.md was broken in majority of the files that I have read, I fixed it in addition to correcting some typos.
* Update README.md
* Update README.md
* fixed typos and broken links
* Completed chapter one review
* Update README.md
* Update app.py
* Update virtual-device.md
* worked on the request
* fixed up the apps
* Update README.md