Add README.md based on README

This is merely just a preview of one of the first sections so you can see what I've done so far with it.

It also includes the build status icon I was talking about.

Once you get a look at this and think it's going the right way I can close this PR and finish it up and send another PR.

Click this link to see the markdown view:

https://github.com/claudijd/ike-scan/blob/80a362973282e6a8d97df490e5bf706f7a113a5c/README.md