This incorporates six commits from jimpo's PR 12254 for BIP158:
254c85b68 bench: Benchmark GCS filter creation and matching.
f33b717a8 blockfilter: Optimization on compilers with int128 support.
53e7874e0 blockfilter: Simple test for GCSFilter construction and Match.
558c536e3 blockfilter: Implement GCSFilter Match methods.
cf70b5500 blockfilter: Implement GCSFilter constructors.
c454f0ac6 blockfilter: Declare GCSFilter class for BIP 158 impl.
Depends on D2799