New features:
- Data validation: input message and error alert
- Preserve build in names
- Hidden names
- Underline for comment text
- Chart objects in worksheets
- Images on chart sheets

Improvements:
- Dates pattern handling

Bug fixes:
- Reading Unicode characters for big Excel files
- String values in cells bigger than 255 chars
- Load Asian phonetic blocks
- Unicode chars in comment text
- + unary operator for formulas
- Default background color for cells
- Keep previous number format when inserting values from a list
- Number date format when inserting values from list
- Default print area
- Load row height
- Load hyperlink description
- Load unknown objects
- Load chart area font settings
- Load legend settings
- Load series background set to None
- Saving the formula result not the formula expression when saving a CSV file