* plugin for authenticating clients based on certificates
* create ca, server and device keys and certificates. certificate auth plugin verification (non linted)
* adding documentation for the various cli scripts and the CertificateAuthPlugin
* post_init was not running on client config. cafile, keyfile, certfile are part of the connection section
* 'broker' section of client config can be empty, but connection will either be provided by the user or the default