Audit details (#1)

Audit details

* Audit logs and broadcasts accept `details` whose values are included as log tags and MRSK_* env vars passed to the broadcast command
* Commands may return execution options to the CLI in their args list
* Introduce `mrsk broadcast` helper for sending audit broadcasts
* Report UTC time, not local time, in audit logs. Standardize on ISO 8601 format

lib/mrsk/commander.rb

@@ -84,8 +84,8 @@ class Mrsk::Commander
     Mrsk::Commands::Accessory.new(config, name: name)
   end
 
-  def auditor(role: nil)
-    Mrsk::Commands::Auditor.new(config, role: role)
+  def auditor(**details)
+    Mrsk::Commands::Auditor.new(config, **details)
   end
 
   def builder