Added "tn-" prefix to testnet nodes.

testnet/docker-compose.yml

@@ -3,7 +3,7 @@ version: '3'
 services:
 
   tnbitcoin:
-    container_name: bitcoin-node
+    container_name: tn-bitcoin-node
     image: kylemanna/bitcoind
     volumes:
       - ./btcnode:/bitcoin
@@ -29,7 +29,7 @@ services:
         ipv4_address: 172.0.0.10
 
   lightning:
-    container_name: lightning-node
+    container_name: tn-lightning-node
     image: nicolasdorier/clightning:v0.6.2-3
     volumes:
       - ./clnode:/root/.lightning