#218 IP subnet Accesors defined wrong if LowIP is not subnet base

[John A. Sullivan III]

If we define an IP Accessors as a subnet but set the Low IP address as a value other than the subnet base, the subnet mask is overwritten and set to 32 bits making it a single IP Accessor. This is done without warning. The user should be advised, apprised of the possible proper settings, and returned to the current field for corrections.