add version, domain and workstation fields

Add version support from jh125486
Add workstation and domain support from jh125486
Enable to extract domain from username

version.go

@@ -0,0 +1,20 @@
+package ntlmssp
+
+// Version is a struct representing https://msdn.microsoft.com/en-us/library/cc236654.aspx
+type Version struct {
+	ProductMajorVersion uint8
+	ProductMinorVersion uint8
+	ProductBuild        uint16
+	_                   [3]byte
+	NTLMRevisionCurrent uint8
+}
+
+// DefaultVersion returns a Version with "sensible" defaults (Windows 7)
+func DefaultVersion() Version {
+	return Version{
+		ProductMajorVersion: 6,
+		ProductMinorVersion: 1,
+		ProductBuild:        7601,
+		NTLMRevisionCurrent: 15,
+	}
+}