code: func (store FileStore) UseIn(composer *tusd.StoreComposer) {
  	composer.UseCore(store)
  	composer.UseGetReader(store)
  	composer.UseTerminater(store)
  	composer.UseLocker(store)
  	composer.UseConcater(store)
  	composer.UseLengthDeferrer(store)
  }
docs: // UseIn sets this store as the core data store in the passed composer and adds
  // all possible extension to it.