Release v1.4 of Zcash FPGA acceleration engine

Update of v1.3 release to include higher performance multiplier with modular reduction (used in bls12-381 coprocessor), and other small bug fixes.
v1.4.1 has bug fix for AWS build with new multiplier
v1.4.2 has bug fix for new multiplier RAM if loading from init file

Release v1.3 of Zcash FPGA acceleration engine

This contains the Equihash verification engine, secp256k1 ECDSA engine, and bls12-381 coprocessor (which supports all operations up to Fp^12 required for point multiplication and the optimal ate pairing).