Update 'Architecture'

Architecture.md

@@ -15,5 +15,8 @@ server/upstream | try to serve stuff based on args from handler | html,server/{c
 server/utils | general purpose functions |
 server/version | just store the program version | 
 
+## Concepts
 
-Each package creates a client that others can use ... e.g. gitea -> GiteaClient, certificates -> AcmeClient, ...
+Each package creates a client that others can use ... e.g.:
+- server/gitea -> GiteaClient
+- server/certificates -> AcmeClient, ...