Update sampleapps/botframework to use opent2t library

[tjaffri]

Currently the sampleapps/botframework/ sample is just parsing commands and not actually invoking any translator. We need to add code approximately here to use the opent2t library, similar to how the cloud sample does it here.

We also should not have to download the entire git repo as we do in git.js and towards the end of app.js. All that should be cleaned up to use the official methods in the opent2t library.