- as the __popcnt64 builtin is not present on 32-bit Windows, the build   failed; this commit fixes the problem using the __popcnt builtin on   32-bit Windows
- as the __popcnt64 builtin is not present on 32-bit Windows, the build
  failed; this commit fixes the problem using the __popcnt builtin on
  32-bit Windows

jandom/rdkit,greglandrum/rdkit,rvianello/rdkit,rdkit/rdkit,ptosco/rdkit,greglandrum/rdkit,adalke/rdkit,rdkit/rdkit,rdkit/rdkit,adalke/rdkit,rvianello/rdkit,rvianello/rdkit,ptosco/rdkit,adalke/rdkit,ptosco/rdkit,bp-kelley/rdkit,ptosco/rdkit,greglandrum/rdkit,rvianello/rdkit,bp-kelley/rdkit,bp-kelley/rdkit,adalke/rdkit,bp-kelley/rdkit,rvianello/rdkit,rdkit/rdkit,adalke/rdkit,adalke/rdkit,greglandrum/rdkit,adalke/rdkit,rvianello/rdkit,jandom/rdkit,jandom/rdkit,greglandrum/rdkit,rdkit/rdkit,rdkit/rdkit,jandom/rdkit,bp-kelley/rdkit,adalke/rdkit,rvianello/rdkit,ptosco/rdkit,bp-kelley/rdkit,ptosco/rdkit,bp-kelley/rdkit,jandom/rdkit,greglandrum/rdkit,jandom/rdkit,rdkit/rdkit,greglandrum/rdkit,jandom/rdkit,ptosco/rdkit,ptosco/rdkit,rdkit/rdkit,rvianello/rdkit,jandom/rdkit,greglandrum/rdkit,bp-kelley/rdkit