message: Make lint-includes.sh work from any directory
diff: export LC_ALL=C
  IGNORE_REGEXP="/(leveldb|secp256k1|univalue)/"
  +# cd to root folder of git repo for git ls-files to work properly
  +cd "$(dirname $0)/../.." || exit 1
  +
  filter_suffix() {
  git ls-files | grep -E "^src/.*\.${1}"'$' | grep -Ev "${IGNORE_REGEXP}"
  }
  