bitpacking 0.8.4

Fast integer compression/decompression via SIMD bit-packing. Port of simdcomp to rust.
Documentation
# bitpacking 0.8.2

- Much much faster compilation in debug mode. (#20)

# bitpacking 0.8.1

- Bugfix for arrays requiring 32-bits. (#17)
- Added proptest (thanks to @danburkert)
- Switched to edition 2018

# bitpacking 0.8.0

Enabling 1x, 4x, and 8x bitpacking based on feature flags.
For backward compatibility, by default, all 3 are enabled.