Added certificate commands to toolkit guide.
Applied formatting and organizational changes from PR review.
This closes
@@ -195,6 +195,7 @@ In order to facilitate the secure setup of NiFi, you can use the `tls-toolkit` c
* <<toolkit-guide.adoc#wildcard_certificates,Wildcard Certificates>>
* <<toolkit-guide.adoc#tls_operation_modes,Operation Modes: Standalone and Client/Server>>
* <<toolkit-guide.adoc#tls_intermediate_ca,Using An Existing Intermediate Certificate Authority>>
+* <<toolkit-guide.adoc#additional_certificate_commands,Additional Certificate Commands>>
[[user_authentication]]
