message: Add getter for last committed hash in Merkle storage
diff: @@ -569,6 +569,13 @@ impl MerkleStorage {
  fn string_to_key(&self, string: &String) -> ContextKey {
  string.split('/').map(str::to_string).collect()
  }
  +
  + pub fn get_last_commit_hash(&self) -> Option<EntryHash> {
  + match &self.last_commit {
  + Some(c) => Some(self.hash_commit(&c)),
  + None => None
  + }
  + }
  }
  #[cfg(test)]
  