Readme updates #31

@cleverness
I'd like to hear your thoughts on the ideas below for the readme file.

• Plugin website > Move to GitHub Wiki or update website after each update. We can create a website link on the GitHub Wiki.
  • We can add documentation on the wiki as well, example: https://github.com/JoryHogeveen/view-admin-as/wiki
• Credits as a list item (more compact)
• Licence can be removed since there is a licence file within the plugin. All plugins on WP.org are GPL compatible.
• FAQ
  • Apply correct markup
  • Bug reporting: Change links to GitHub so contributors can help if possible.
  • Add numbers for FAQ questions