docs(copm): Add sequence diagrams for COPM primitives

Primary change: adds mermaid sequence diagrams for
how COPM primitives are used in asset transfer, asset
exchange, and data sharing to copm-core README

Signed-off-by: Jennifer Bell <jenniferlianne@gmail.com>

packages/cacti-copm-core/README.md

@@ -18,10 +18,151 @@ Yarn:
     yarn add --exact @hyperledger-cacti/cacti-copm-core
 
 
+## Data Sharing
+
+### COPM Command
+ - getVerifiedState
+
+### Figure: Data Sharing with getVerifiedState
+
+```mermaid
+sequenceDiagram
+    participant Alice
+    participant COPM gRPC A
+    participant Ledger A
+    participant Relay A 
+    participant Relay B
+    participant Ledger B as Ledger B 
+    Alice->>COPM gRPC A: getVerifiedState for State X on Ledger B
+    activate COPM gRPC A
+    COPM gRPC A->>Relay A: Read State X on Ledger B
+    activate Relay A
+    Relay A->>Relay B: Read State X
+    activate Relay B
+    Relay B->>Ledger B: Read State X
+    activate Ledger B
+    Ledger B->>Ledger B: Read State X
+    Ledger B->>Relay B: Return signed State X
+    deactivate Ledger B
+    Relay B->>Relay A: Return signed State X
+    deactivate Relay B
+    Relay A->>COPM gRPC A: Return signed State X
+    deactivate Relay A
+    COPM gRPC A->>Ledger A: Verify signature
+    activate Ledger A
+    Ledger A->>Ledger A: Verify signature
+    Ledger A->>COPM gRPC A: Signature Verified
+    deactivate Ledger A
+    COPM gRPC A->>Alice: Return State X
+    deactivate COPM gRPC A
+```
+
+## Asset Transfer
+
+ - Asset changes networks
+ - Asset burnt on Ledger A, minted on Ledger B
+ - Introduces 2 ledger data types:
+    - Pledge
+       - A record created on Ledger A when an asset is burnt
+       - Contains details about the asset, who it is promised to 
+   - Claim
+        - A record created on Ledger B when the pledged asset is minted
+### COPM Commands
+  - Pledge
+  - ClaimPledge
+
+### Figure: Asset Transfer Pledge and ClaimPledge
+
+
+```mermaid
+sequenceDiagram
+    actor Alice
+    actor Bob
+    participant System A 
+    participant Asset
+    participant System B
+    note right of System B:System: Ledger, <br/>Relay, COPM gRPC
+    Alice->>Bob: Would you like my Asset?
+    Bob->>Alice: Yes, please.
+    Alice->>System A: Pledge Asset
+    activate System A
+    System A->>System A: Create Pledge
+    destroy Asset
+    System A-xAsset: Burn
+    deactivate System A
+    Alice->>Bob: You can claim it now!
+    Bob->>System B: Claim Pledge
+    activate System B
+    rect rgb(191, 223, 255)
+      System B->>System A: Read Pledge on System A
+      activate System A
+      note right of System B: A cross-network <br/>'Data Sharing' flow
+      System A->>System A: Read Pledge
+      System A->>System B: Return signed pledge
+      deactivate System A
+    end
+    System B->>System B: Create Claim
+    create participant PB as Asset
+    System B->>PB: Mint
+    deactivate System B
+```
+
+## Asset Exchange
+
+ - Assets stay where they are
+ - Two parties swap asset ownership of two assets
+   - Assets can be on different networks
+ - Uses HTLC (Hash Time Lock Contract) 
+ - Both parties have visibility of both assets/networks
+ - No inter-network communication needed 
+    - no relays 
+
+### COPM Commands
+ - Lock
+ - ClaimLock 
+
+### Figure: Asset Exchange with Lock and ClamLock
+
+```mermaid
+sequenceDiagram
+    actor Alice
+    actor Bob
+    participant Token System
+    participant Bond System
+    note right of Bond System: System: Ledger and COPM gRPC
+    Alice->>Bob: Would you like to trade my Tokens for your Bond?
+    Bob->>Alice: Yes, please.
+    Alice->>Token System: Lock Tokens
+    activate Token System
+    Token System->>Token System: Lock Tokens
+    deactivate Token System
+    Bob->>Bond System: Lock Bond
+    activate Bond System
+    Bond System->>Bond System: Lock Bond
+    deactivate Bond System
+    Alice->>Bob: I've locked my Tokens, the secret is X.
+    Bob-->>Token System: Sees Tokens are Locked
+    Bob->>Alice: I've locked my Bond, the secret is Y.
+    Alice-->>Bond System: Sees Bond is Locked
+    Alice->>Bond System: Claim Lock for Bond with secret Y
+    activate Bond System
+    Bond System->>Bond System: Verify Lock
+    Bond System->>Bond System: Change Bond owner to Alice
+    deactivate Bond System
+    Bob->>Token System: Claim Lock for Tokens with secret X
+    activate Token System
+    Token System->>Token System: Verify Lock
+    Token System->>Token System: Change Token owner to Bob
+    deactivate Token System
+```
+
+
 # Development
 
 When implementing a new distributed ledger, the following interfaces must be implemented:
 
 - DLTransactionContext:  Implements running a transaction on the local network
 - DLRemoteTransactionContext: Uses the weaver relays to run a transaction on another network
-- DLTransactionContextFactory: Factory to return either local or remote context for the specific DLT.
+- DLTransactionContextFactory: Factory to return either local or remote context for the specific DLT.
+
+