Not to reset already defined types when reimporting

[kimsama]

Whenever reimport a spreadsheet all types are reset, even the changes are adding a few columns or change of column name.

[quan-nguyen]

in GoogleMachineEditor.cs this code is not good

if (headerDic != null && headerDic.ContainsKey(cell.Value))
                    machine.HeaderColumnList.Add(new HeaderColumn { name = cell.Value, type = headerDic[cell.Value].type });

[kimsama]

Could you explain it for more details? What exactly you means? Any suggestion or good idea may appreciate.

[kimsama]

Fixed in issue #19