+ XLS BIFF8: added DATE and TIME worksheet functions to RPN formula
* Allow writing formulas,numbers etc using cardinals increasing row/column limits for formats that support it.
* Add checks for text cell size limits when writing xls, xml. If exceeded, cell text will be truncated (better than corrupting the xls file - e.g. try to open it with Excel 2002 - as happens now with xls format)
* Formats that use fpspreadsheet zip have extra checks to prevent crashes for invalid zip dates
+ Use FPC built-in zip format when using FPC 2.7.1+ as it has fixes/improvements (e.g. zip64 support)
+ Added FPCUnit test suite to test reading and reading writing files. For now uses BIFF8 xls; contributions for other formats and more tests welcome. See the tests subdirectory.
+ Add link to msodumper tool for reference/debugging/troubleshooting .xls output
Fixes Mantis bugtracker issue #25388
git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@2857 8e941d3f-bd1b-0410-a28a-d453659cc2b4
