a username is not checked first against the AD instead of local SAM

- a given username without any appended domain is now verified against the domain the machine is member of
- if the domain is the Local Machine than the user is Local verified
- if the domain is contoso.local a username is verified against contoso.local
- if a domain is appended to the username like username@osotnoc.local than the user id verified against osotnoc.local

pGina/src/Service/Impl/Service.cs

@@ -1358,7 +1358,15 @@ private Dictionary<string, string> SplitDomainfromUsername(string username, stri
                 if (String.IsNullOrEmpty(domain))
                 {
                     ret["username"] = username;
-                    ret["domain"] = Environment.MachineName;
+                    string domainmember = Abstractions.WindowsApi.pInvokes.GetMachineDomainMembershipEX();
+                    if (string.IsNullOrEmpty(domainmember))
+                    {
+                        ret["domain"] = Environment.MachineName;
+                    }
+                    else
+                    {
+                        ret["domain"] = domainmember;
+                    }
                 }
             }