netCDF classic or 64-bit offset files that have a UINT32_MAX flag for
large last record size of a variable that has values larger than 1
byte. This problem had previously been fixed for *writing* such data,
but was only tested with an ncbyte variable. Fixed test to
demonstrate problem and the fix.
More updates to chunking documentation, cosmetic fixes for some
"--option=" documentation that doxygen turns into mdash.
