• added universal newlines mode ("U") to addfile and shasum
  -- based on Python Universal Newlines concept
  -- newlines identical across MacOS, DOS, and UNIX
  -- will deprecate portable mode ("p") in future
  -- "U" mode is cleaner and more efficient
  
• enhanced performance
  -- reduced number of dynamic memory allocations
  -- sped up addfile method with use of C code
  -- ref. SHA.xs (_addfilebin and _addfileuniv)
  
• eliminated experimental -M option in favor of new -R option
  -- reverses order of digest module preference
  -- undocumented: for test and development use only
  
• sealed memory leak in SHA.xs
  -- arose only with SvPVbyte exceptions during eval
  
• patched inheritence bug (ref: rt.cpan.org #94830)
  -- use sv_isobject/sv_derived_from instead of sv_isa
  
• added 'allocated' flag to SHA structure (ref. src/sha.h)
  -- to guard against Perl double frees