Misc changes from the flakes branch

.gitignore

Makefile.config.in

src/libexpr/eval.hh

src/libstore/build.cc

src/libstore/builtins/buildenv.cc

src/libstore/http-binary-cache-store.cc

src/libstore/local-store.cc

src/libstore/nar-info-disk-cache.cc

src/libstore/nar-info-disk-cache.hh

src/libstore/parsed-derivations.cc

src/libstore/parsed-derivations.hh

src/libstore/profiles.cc

src/libstore/profiles.hh

src/libstore/sqlite.cc

src/libstore/sqlite.hh

src/libstore/store-api.hh

src/libutil/hash.hh

src/libutil/util.hh

src/nix-env/nix-env.cc

tests/binary-cache.sh