ce60785b26 Introduce SECP256K1_B macro for curve b coefficient (Pieter Wuille)
4934aa7995 Switch to exhaustive groups with small B coefficient (Pieter Wuille)
Pull request description:
This has the advantage that in the future, multiplication with B can be done using `secp256k1_fe_mul_int` rather than the slower `secp256k1_fe_mul`.
ACKs for top commit:
real-or-random:
ACK ce60785b26 also ran the exhaustive tests with the group of size 7
apoelstra:
ACK ce60785b26
Tree-SHA512: 006041189d18319ddb9c0ed54e479f393b83ab2a368d198bd24860d1d2574c0c1a311aea24fbef2e74bb7859a687dfc803b9e963e6dc5c61cb707e20f52b5a70