make pool_new() the default for new pool instances

use the simplest function to get a new pool..
DHCP functions, state and FSM cache related funs

More code for very different aspects, dhcp mangling and also FSM pid
resolution via a cache process..
Basic server states got into the gen_fsm

After figuring out what the server states might be the necessary
gen_fsm functions were to be built.
supervisor stubs for dynamic children FSM setup