Start reformatting the Readme page

Still to do:
- Readme work so we can parse it on EDD.com
- Distribution for it on edd.com
- gotvat.com site setup (to explain the 2015 mess and show the options for EDD: this plugin or the VAT one)
- remove EU countries from dropdown (if and only if b2b is disabled)
- offer ability for b2b to be enabled/disabled, and if so show on checkout form VAT validation
- offer ability to hide/show checkbox always, never, or only if IP address != billing address.
- add link to EDD core possible on tax page (up for discussion)

Will move these to GitHub issues for each later