Use Translator class instead of DeepLClient

[morsssss]

My impression is that we want to encourage people to use Translator if they're just doing translations. Is that right?

If not, please feel free to trash this PR :)

[BriannaDelgado]

No - Translator is the old client we used while DeepLClient is the new version that supports all of the APIs. Users should utilize DeepLClient over Translator

[morsssss]

Thanks for letting me know! Now changing Translators to DeepLClients elsewhere