Add AVX2 implementation of Twofish; impl. utilizes the vpgatherdd instructions for vectorized table lookups

NOTE: slower than AVX implementation and 2-way & 3-way implementations on Intel Haswell.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add AVX2 implementation of Twofish (this impl. does not use vpgatherdd)

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Add AVX2 (vpgatherdd) implementation of Blowfish

Note: slower than 4-way and AVX implementations on Intel Haswell.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>