Add support F field

[Koos1]

Please add after: case "M": return DbfColumnType.Memo;
case "F": return DbfColumnType.Number;

[SlightlyMadGargoyle]

This seems to have been added in b32ed07

[valmans]

I dont know where to post this, i used a old version and i updated today, but i cannot dind how to get a memo field, i used the function GetMemField, is another new function or other method?

Best regards.