v0.3.0 (2021-06-01)

• Rename dataset with prefix r2rtf to avoid conflict of other namespace
• Enable special place holder "-----" in page_by variable to suppress line displayed
  in page_by variable (ref Example 2 in vignette/example-pageby-groupby)
• New experimental function rtf_convert_format.
• New argument pageby_row in rtf_body to display first row instead of page_by variable when pageby_row = "first_row"
• New argument subline_by in rtf_body to display subline by an variable.
• New argument text_indent_reference to allow user to control reference of indent from page margin or table border (#12)
• New internal function rtf_subset to subset an rtf table object.
• Bug fix group_by can be used when page_by=NULL.
• Bug fix page_by can not sort format style in rtf_body
• Bug fix ensure consistent font size with blank cell (#14)