message: use Subproject hash for folly and fizz
  Summary:
  this is how we do dependencies
  fixes
diff: @@ -62,6 +62,7 @@ fi
  ### configure necessary build and install directories
  +START_DIR=$(pwd)
  cd $BUILD_DIR || exit
  BWD=$(pwd)
  DEPS_DIR=$BWD/deps
  @@ -176,6 +177,10 @@ function setup_folly() {
  if [ ! -d "$FOLLY_DIR" ] ; then
  echo -e "${COLOR_GREEN}[ INFO ] Cloning folly repo ${COLOR_OFF}"
  git clone https://github.com/facebook/folly.git "$FOLLY_DIR"
  + cd "$FOLLY_DIR"
  + git fetch
  + FOLLY_REV=$(sed 's/Subproject commit //' "$START_DIR"/build/deps/github_hashes/facebook/folly-rev.txt)
  + git checkout "$FOLLY_REV"
  if [[ -z "${MVFST_SKIP_SYSTEM_DEPENDENCIES-}" ]]; then
  echo -e "${COLOR_GREEN}[ INFO ] install dependencies ${COLOR_OFF}"
  if [ "$Platform" = "Linux" ]; then
  @@ -231,8 +236,11 @@ function setup_fizz() {
  if [ ! -d "$FIZZ_DIR" ] ; then
  echo -e "${COLOR_GREEN}[ INFO ] Cloning fizz repo ${COLOR_OFF}"
  git clone https://github.com/facebookincubator/fizz "$FIZZ_DIR"
  - echo -e "${COLOR_GREEN}[ INFO ] install dependencies ${COLOR_OFF}"
  fi
  + cd "$FIZZ_DIR"
  + git fetch
  + FIZZ_REV=$(sed 's/Subproject commit //' "$START_DIR"/build/deps/github_hashes/facebookincubator/fizz-rev.txt)
  + git checkout "$FIZZ_REV"
  echo -e "${COLOR_GREEN}Building Fizz ${COLOR_OFF}"
  mkdir -p "$FIZZ_BUILD_DIR"
  cd "$FIZZ_BUILD_DIR" || exit
  