RTPHost moved from src/transport to src/nodes/

HOST MODELS MUST ALWAYS BE PLACED INTO nodes/!!! (or under an example simulation)
TEMP FIX: node-level routingFile cannot be supported since routingTable uses "like"!!!

routingFile=routingFile is rejected because IRoutingTable doesn't have
such parameter; and it cannot be added to IRoutingTable because not
all routing table types support it (in fact, only IPv4).

TODO RECONSIDER WHAT TO DO TO CLEAN UP THIS!

PROBLEM SEEMS TO BE THAT NODEBASE WAS SILENTLY TURNED INTO "GENERICNODEBASE"
FROM "IPvNODEBASE". MAYBE: RESTORE OLD NODEBASE AS IPv4NODEBASE, AND CREATE
A NEW GENERICNODEBASE. STANDARDHOST TO USE IPv4NODEBASE!
USE GENERICNODEBASE ONLY HERE REALLY REALLY NEEDED.
I.E. IN SOME EXAMPLE SIMULATIONS.