Add remove member

Group-chat-feature-(design-draft).md

@@ -146,7 +146,20 @@ So, if Alice wants to ban Denys, she had to propose a vote with the sequence num
 5. When we are sure that someone is synched, remove erased=time::now() and sync with other user's devices
 6. All devices owned by the user can now erase the repository and related files
 
-**TODO, determine how this will work**
+## Remove a device from a conversation
+
+This is the only part that MUST have a consensus to avoid conversation's split, like if two members kick each others from the conversation, what will see the third one?
+
+This is needed to detect revoked devices, or simply avoid to get unwanted people present in a public room. The process is pretty similar between a member and a device:
+
+*Alice removes Bob*
+
+Note: Alice MUST be admins to vote
+
++ First, she votes for ban Bob. To do that, she creates the file in /votes/members/uri_bob/uri_alice (members can be replaced by devices for a device) and commit
++ Then she checks if the vote is resolved. This means that >50% of the admins agree to ban Bob (if she is alone, it's sure it's more than 50%).
++ If the vote is resolved, files into /votes can be removed, all files for Bob in /members, /admins, /CRLs, /devices can be removed (or only in /devices if it's a device that is banned) and Bob's certificate can be placed into /banned/members/bob_uri.crt (or /banned/devices/uri.crt if a device is banned) and committed to the repo
++ Then, Alice informs other users (outside Bob)
 
 # Used protocols
 
@@ -180,12 +193,18 @@ Moreover editing messages will be possible! (`commit --fixup`)
 
 ```
 /
- - Admins (public keys)
- - Members (public keys)
- - Devices (certificates of authors to verify commits)
- - Banned
-   - Devices
-   - Accounts
+ - invited
+ - admins (public keys)
+ - members (public keys)
+ - devices (certificates of authors to verify commits)
+ - banned
+   - devices
+   - members
+ - votes
+    - members
+        - uri
+    - devices
+        - uri 
  - CRLs
 ```