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 .
This PR adds the common OSS changes for adding support for Consul Namespaces,
which is going to be a Nomad Enterprise feature. There is no new functionality
provided by this changeset and hopefully no new bugs.
