* implementation of the fast subgroup check for bls12_381

* add a bench

* subgroup check for g1

* subgroup check modifications

* remove useless test

* fmt

* need the last version of arkworks/algebra

* remove Parameters0

* using projective points is more efficient

* use of projective coordinates in G2

* fmt

* documentation on the constants and the psi function

* references for algorithms of eprint 2021/1130

* fmt

* sed ^ **

* minor improvement

* fmt

* fix Cargo toml

* nits

* some cleanup for g1

* add the beta test back

* fmt

* g2

* changelog

* add a  note on the Cargo.toml

* nits

* avoid variable name conflicts

* add the early-out optimization

Co-authored-by: weikeng <w.k@berkeley.edu>