Release Notes for PDL-IO-HDF5 0.64 --------------------------

General Notes:

 * This is an update release to PDL::IO::HDF5 with
   improved platform detection and build process.

 * New features and tests (thanks to Andrew Benson)

Highlights:

 * New features:
   - Unlinking of datasets
   - Extensible datasets
   - Creation of scalar references
   - Automatic dereferencing of scalar references
   - Support for longlong integer attributes and datasets

 * Improved packaging, platform and build:
   - Better HDF5 library detection on cygwin
   - Added longlong tests
   - Other cleanup and fixs
