v1.9.0

Features

• Added support for merging cells. To merge a range of cells together, call Spreadsheet.MergeCells with the range as the parameter.
• Added initial support for auto filtering. For now it can be enabled by setting WorksheetOptions.AutoFilter. Thanks to @mderubertis-velan for the contribution!
• Added Spreadsheet.TryAddDataValidation as an alternative to Spreadsheet.AddDataValidation. TryAddDataValidation will return false if attempting to add too many data validations to a worksheet, while AddDataValidation will throw an exception.
• Added utility method SpreadsheetUtility.GetColumnName. It returns the column name from a column number, e.g. column number 1 will return column name A.

Breaking changes

• Spreadsheet.AddDataValidation will now throw an exception if attempting to add more than 65534 data validations to a worksheet (Excel limitation).