Add a few words on the admin interface.

TODO.md

@@ -11,6 +11,8 @@
 - user interface: enables to update the email address
 - zone-wise indications to help people configure their zone for specific uses (web, mail)
 - explanations and static content in general should be written using some kind of templates, not directly in Halogen
+- admin interface: enable administrators to ask for users' info and show zones
+- admin interface: perform a few more administrative operations (*TBD*)
 
 # Tests
 
@@ -25,6 +27,7 @@
 - hide logs by default
 - show a big button on disconnection
 - *maybe* notifications should disappear after a few seconds
+- admin interface: basically just rewrite the whole thing, it's a mess
 
 # General note