Relase 2.0.0 RC2

Changes from 2.0.0.rc1 to 2.0.0.rc2

• New compatibility with MinGW32/64. See #302.

• Improved support for AArch64 (aka ARM64), ARMv7l, ARMv6l and powerpc64le.
  See #306. Thanks to Alexandr Romanenko, Mark Kittisopikul and Mosè Giordano
  from the Julia packaging team for their help.

• BloscLZ updated to 2.4.0. Aligned access in ARM has been enabled, as well
  as other performance improvements. Expect much better performance,
  specially on ARM platforms (like Apple Silicon).

• Zstd sources updated to 1.5.0.

• zlib-ng sources updated to 2.0.3.