init vmc validator

Former-commit-id: 64d7a424c48c44917ad7439164f05372582ef857 [formerly 63fa2f70fe30ce4403157ab87e4344a0b5681163]
Former-commit-id: ed84eeb88b0a8b705fdf4c3f6c4a65053c58532e

sharding/client.go

@@ -72,6 +72,13 @@ func (c *Client) Start() error {
 		return err
 	}
 
+	// TODO: Deposit 100ETH into the validator set in the VMC. Checks if account
+	// is already a validator in the VMC (in the case the client restarted)
+	// Once that's done we can subscribe to block headers
+	if err := initVMCValidator(c); err != nil {
+		return err
+	}
+
 	// Listens to block headers from the geth node and if we are an eligible
 	// proposer, we fetch pending transactions and propose a collation
 	if err := subscribeBlockHeaders(c); err != nil {

sharding/vmc.go

@@ -66,3 +66,11 @@ func initVMC(c *Client) error {
 
 	return nil
 }
+
+// initVMCValidator checks if the account is a validator in the VMC. If
+// the account is not in the set, it will deposit 100ETH into contract.
+func initVMCValidator(c *Client) error {
+
+	// TODO: Implement
+
+}