Add Mediation-Flows.md (#119)

Signed-off-by: Fabio Pinheiro <fabiomgpinheiro@gmail.com>

Mediation-Flows.md

@@ -0,0 +1,63 @@
+# Mediator
+
+## Accept Invitation (Flow Diagram)
+
+```mermaid
+sequenceDiagram
+  participant Alice
+  participant Mediator
+  participant DID Resolver
+
+  note over Alice: Mediation client or Mediated Agent
+
+  rect rgb(0, 120, 255)
+    note right of Alice: Alice accepts the invitation and register for a mailbox.
+    Alice->>+Mediator: Register (HTTP)
+    Mediator->>+DID Resolver: Ask for Alice DID document
+    DID Resolver-->>-Mediator: DID document 
+    note over Mediator: Confirm the identity
+    Mediator-->>-Alice: Registration done
+    note over Alice: Alice updates his DID document (adding serviceEndpoint)
+  end
+```
+
+---
+
+## Send message through the mediator (Flow Diagram)
+
+**Alice wants to send a message to Bob:**
+
+```mermaid
+sequenceDiagram
+  participant Alice
+  participant DID Resolver
+  participant Mediator
+  participant Bob
+
+  note over Bob: Mediation client or Mediated Agent
+
+  rect rgb(0, 120, 255)
+    Alice->>+DID Resolver: Ask for Bob DID document
+    DID Resolver-->>-Alice: DID document
+    note over Alice: Find the serviceEndpoint of Bob
+    note over Alice: Mediation Request
+    Alice->>+Mediator: Forward {Message to Bob}
+
+    opt Depending on the registration (config)
+      Mediator->>-Bob: Notify or send the playload to Bob
+      note over Mediator,Bob: This can be an Email, Webhook, Push API, WebSocket (that is already open), etc
+    end
+  end
+
+  rect rgb(0, 120, 255)
+    opt Bob read Message.
+      Bob->>+Mediator: Get message
+      opt If the cache is too old
+        Mediator->>+DID Resolver: Get updated Bob's DID document
+        DID Resolver-->>-Mediator: DID document
+      end
+      note over Mediator: Confirm the identity
+      Mediator-->>-Bob: {Message to Bob} (the playload of the Forward Message)
+    end
+  end
+```

README.md

@@ -28,7 +28,9 @@ graph LR
 For the fastest answers, join the [#atala-mediator][Link-Discord-Mediator] channel in the official Atala Discord and ask your questions, or just chat with other Atala developers and pioneers!
 
 
-# Table of contents:
+**More documentation:**
+- [LICENSE](LICENSE) - Apache License, Version 2.0
+- [Mediation Flows](Mediation-Flows.md) - Examples of mediation flows
 - [Mediator Purpose](#Description)
 - [Protocols Supported](#Protocols)
   - [Mediator Protocol State and Flow](Coordinate-Mediation-Protocol.md)