Move link definitions in readme to where they're used

Instead of keeping them all at the end of the document, making for lots
of scrolling if reading/editing the raw markdown.
Add updating section to readme
Change license to WTFPL (Do What The Fuck You Want To Public License)

Instead of using a slightly customized/stripped down variant of MIT,
let's use a standard license, that let's you do what the fuck you want
with the project. Like the customized MIT license's intent was.