datetimeoffset 0.2.1

New features

• format_exiftool() formats datetime strings as expected by the command-line tool exiftool (#54).
• as_datetimeoffset.integer() and as_datetimeoffset.numeric()
  coerce numeric values as the new datetimeoffset() objects year field (#53).

Bug fixes and minor improvements

• format_iso8601() has new argument mode which supports "normal" and "xmp".

  • XMP metadata datetimes are a strict subset of ISO 8601 datetimes

• as_datetimeoffset.character() now parses pdfmark datetimes of the form D:YYYYmmddHHMMSSZ00'00' (#56)

• Skip a test on CRAN which was failing on r-oldrel-windows-ix86+x86_64 (#52)