Feature/multiple validator endpoints (#583)

* Rust half done

* Removed the temporary 'test'

* Using multiple validator endpoints in the javascript client

* Dont attempt any switches with a single validator endpoint

* Removed the unused temporary function

* Updated validator-client version

mixnode/src/node/mod.rs

@@ -89,10 +89,10 @@ impl MixNode {
     // TODO: ask DH whether this function still makes sense in ^0.10
     async fn check_if_same_ip_node_exists(&mut self) -> Option<String> {
         let validator_client_config = validator_client_rest::Config::new(
-            self.config.get_validator_rest_endpoint(),
+            self.config.get_validator_rest_endpoints(),
             self.config.get_validator_mixnet_contract_address(),
         );
-        let validator_client = validator_client_rest::Client::new(validator_client_config);
+        let mut validator_client = validator_client_rest::Client::new(validator_client_config);
 
         let existing_nodes = match validator_client.get_mix_nodes().await {
             Ok(nodes) => nodes,