Revert "Revert "Revert "Add hostname as node ID."""

This reverts commit 6fe25e58f8.

build.xml

@@ -113,8 +113,6 @@
           failonerror="true">
       <arg value="-role"/>
       <arg value="node"/>
-      <arg value="-id"/>
-      <arg value="${env.HOSTNAME}"/>
       <arg value="-hub"/>
       <arg value="http://${hub.host}:${hub.port}/grid/register"/>
       <arg value="-host"/>