solution: show in log when gets an upstream

src/main/kotlin/io/emeraldpay/dshackle/upstream/Upstream.kt

@@ -3,6 +3,7 @@ package io.emeraldpay.dshackle.upstream
 import io.emeraldpay.grpc.Chain
 import io.infinitape.etherjar.rpc.json.BlockJson
 import io.infinitape.etherjar.rpc.json.TransactionJson
+import org.slf4j.LoggerFactory
 
 class Upstream(
         val chain: Chain,
@@ -10,6 +11,8 @@ class Upstream(
         private val ethereumWs: EthereumWs? = null
 ) {
 
+    private val log = LoggerFactory.getLogger(Upstream::class.java)
+
     val head: EthereumHead = if (ethereumWs != null) {
         EthereumWsHead(ethereumWs)
     } else {
@@ -19,6 +22,6 @@ class Upstream(
     }
 
     init {
-
+        log.info("Configured for ${chain.chainName}")
     }
 }