message: Adds ForceStringAlignment to flatbuffers.
  ForceStringAlignment is useful for memory aligning string fields in flatbuffers.
diff: @@ -1207,6 +1207,11 @@ class FlatBufferBuilder {
  PreAlign(len * elemsize, alignment);
  }
  + // Similar to ForceVectorAlignment but for String fields.
  + void ForceStringAlignment(size_t len, size_t alignment) {
  + PreAlign((len + 1) * sizeof(char), alignment);
  + }
  +
  /// @endcond
  /// @brief Serialize an array into a FlatBuffer `vector`.
  