Switch to a Commander base to allow lazy loading config

lib/tasks/mrsk/registry.rake

@@ -1,18 +1,16 @@
 require_relative "setup"
 
-registry = Mrsk::Commands::Registry.new(MRSK_CONFIG)
-
 namespace :mrsk do
   namespace :registry do
     desc "Login to the registry locally and remotely"
     task :login do
-      run_locally           { execute *registry.login }
-      on(MRSK_CONFIG.hosts) { execute *registry.login }
+      run_locally           { execute *MRSK.registry.login }
+      on(MRSK.config.hosts) { execute *MRSK.registry.login }
     end
 
     desc "Logout of the registry remotely"
     task :logout do
-      on(MRSK_CONFIG.hosts) { execute *registry.logout }
+      on(MRSK.config.hosts) { execute *MRSK.registry.logout }
     end
   end
 end