Plugins are activated using symlinks in $AXZSH/active_plugins
AX-ZSH no longer uses configuration variables ($axzsh_plugins,
$axzsh_default_plugins, $plugins) to configure the list of plugins
to load. Instead, all plugins that should be activated must be
linked into the $AXZSH/active_plugins/ directory.
To simplify the plugin handling, the new "axzshctl" script has been
added: you can use the subcommands "enable-plugin", "disable-plugin",
and "reset-plugins" to enable or disable individual plugins, or to
reset the list of activated plugins to the default plugins.