In most cases (e.g. any of the nmap.socket operations), functions can
take full host and port tables instead of just host.ip and port.number.
This makes for cleaner-looking code and easier extensibility if we
decide to check for a protocol on both TCP and UDP, for instance.
In addition to fitting better (brute library is the verb, creds library
is the noun), this will allow creds.lua to use creds.Account internally
where necessary (see subsequent commits)
Also change old references to string argument "OPEN" into
creds.State.VALID.
In the case of a few of these scripts the only thing that was updated was the example text as the scripts relied on the creds library which handles the strings internally.
