TCPIP connections and DNS lookups channel options

TCP/IP connections and DNS lookups channel options
A number of channel options affect TCP/IP connections and DNS lookups.

See also:
 * affinitylist Option
 * cacheeverything Option
 * cachefailures Option
 * cachesuccesses Option
 * connectalias Option
 * connectcanonical Option
 * daemon Option
 * defaultmx Option
 * defaultnameservers Option
 * dnsforcetemporary Option
 * forwardcheckdelete Option
 * forwardchecknone Option
 * forwardchecktag Option
 * identnone Option
 * identnonelimited Option
 * identnonenumeric Option
 * identnonesymbolic Option
 * identtcp Option
 * identtcplimited Option
 * identtcpnumeric Option
 * identtcpsymbolic Option
 * interfaceaddress Option
 * lastresort Option
 * mailfromdnsverify Option
 * maxconnectionsperdomain Option
 * maxmessagerateperdomain Option
 * mx Option
 * nameservers Option
 * nocache Option
 * nodnsforcetemporary Option
 * nomailfromdnsverify Option
 * nomx Option
 * nonrandommx Option
 * nosocks Option
 * port Option
 * randommx Option
 * sockshost Option
 * socksport Option
 * socksusername Option
 * sockspassword Option
 * socksnoauth Option
 * socksuserpassword Option
 * spfhelo Option
 * spfmailfrom Option
 * spfnone Option
 * spfrcptto Option
 * threaddepth Option
 * Functional group list of channel options