Release 2.5.1

Changes from 2.5.0 to 2.5.1

• Updated to latest C-Blosc2 2.13.1.

• Fixed bug in b2nd.h.

Changes from 2.4.0 to 2.5.0

• Updated to latest C-Blosc2 2.13.0.

• Added the filter INT_TRUNC for integer truncation.

• Added some optimizations for zstd.

• Now the grok library is initialized when loading the
  plugin from C-Blosc2.

• Improved doc.

• Support for slices in blosc2.get_slice_nchunks() when using SChunk
  objects.