Update README.md

README.md

@@ -10,7 +10,10 @@ a calendar server
   - [ ] ICS parsing
     - [x] Datetime parsing
   - [x] Implement PROPPATCH
-- [ ] Access Control
+- [ ] Auth
+  - [ ] Access control
+  - [ ] preparation for different principal types (groups)
+  - [ ] authentication rewrite? (argon2 is very slow for each request)
   - [ ] OIDC support
 - [ ] CardDAV
 - [ ] Locking
@@ -22,3 +25,5 @@ a calendar server
 - [x] Trash bin
   - [x] Hiding calendars instead of deleting them
   - [ ] Restore endpoint
+
+## Relevant RFCs