Incorrent argument checks in HeadingInfo.cs

[zii-dmg]

Constructor:

public HeadingInfo(string programName, string version = null)
{
    if (string.IsNullOrWhiteSpace("programName")) throw new ArgumentException("programName");

Passing string "programName" instead of argument programName value. But HeadingInfo.Empty is creating object with empty string! So I suppose this check should removed and xml comment with exception description.

WriteMessage:

if (string.IsNullOrWhiteSpace("message")) throw new ArgumentException("message");

Same - "message" vs message.