Improves ICS to message conversion API.
Features
- Added the ability to set 'ReferenceAttachment' properties on a 'MapiAttachment' object.
- Added overloaded 'IsMultiContacts' method with the source file name as a parameter.
- Simplified ICS to message conversion API.
- Added 'HtmlFormatOptions.RenderTaskFields' and 'MhtSaveOptions.SaveAllHeaders'.