Fix broken links in readme

The links to github pages were broken but I found I could get to working pages by changing github.com to github.io. It was then redirected to squaremobius.net.

The changelog and tutes link pointed to master that has been rename to main.

README.md

@@ -146,10 +146,10 @@ really only useful for checking the kind and formatting of the errors.
     make coverage
     open file://`pwd`/coverage/lcov-report/index.html
 
-[gh-pages]: http://squaremo.github.com/amqp.node/
-[gh-pages-apiref]: http://squaremo.github.com/amqp.node/channel_api.html
+[gh-pages]: http://www.squaremobius.net/amqp.node/
+[gh-pages-apiref]: http://www.squaremobius.net/amqp.node/channel_api.html
 [nave]: https://github.com/isaacs/nave
-[tutes]: https://github.com/squaremo/amqp.node/tree/master/examples/tutorials
+[tutes]: https://github.com/squaremo/amqp.node/tree/main/examples/tutorials
 [rabbitmq-tutes]: http://www.rabbitmq.com/getstarted.html
-[changelog]: https://github.com/squaremo/amqp.node/blob/master/CHANGELOG.md
+[changelog]: https://github.com/squaremo/amqp.node/blob/main/CHANGELOG.md
 [docker]: https://www.docker.com/