Added "ROM not found." message if specified file is invalid. (#592)

* Added "ROM not found." message if specified file is invalid.

* Fixed styling

* Made message more specific and changed both cases to warnings.

Ryujinx/Program.cs

@@ -75,10 +75,14 @@ namespace Ryujinx
                             break;
                     }
                 }
+                else 
+                {
+                    Logger.PrintWarning(LogClass.Application, "Please specify a valid XCI/NCA/NSP/PFS0/NRO file");
+                }
             }
             else
             {
-                Logger.PrintInfo(LogClass.Application, "Please specify the folder with the NSOs/IStorage or a NSO/NRO.");
+                Logger.PrintWarning(LogClass.Application, "Please specify the folder with the NSOs/IStorage or a NSO/NRO.");
             }
 
             using (GlScreen screen = new GlScreen(device, renderer))