This PR updates the changelog, adds notes the 1.3 upgrade guide, and
updates the connect integration docs with documentation about the new
requirement on Consul ACL policies of Consul agent default anonymous ACL
tokens.
Tweaks to the commands in Consul Connect page.
For multi-command scripts, having the leading `$` is a bit annoying, as it makes copying the text harder. Also, the `copy` button would only copy the first command and ignore the rest.
Also, the `echo 1 > ...` commands are required to run as root, unlike the rest! I made them use `| sudo tee` pattern to ease copy & paste as well.
Lastly, update the CNI plugin links to 1.0.0. It's fresh off the oven - just got released less than an hour ago: https://github.com/containernetworking/plugins/releases/tag/v1.0.0 .
