1. I found at least three. My favorite is that Mycroft is Sherlock Holmes’ older, and some say, smarter, brother. Sherlock Holmes is played on TV by Benedict Cumberbatch, who also played Alan Turing in The Imitation Game, the original name of the Turing test, a test of AI conversation, which is what Mycroft does.
2. One approach has been to gather a selection of commands, label the intent of the commands, use the commands as input to a neural network, and the label as the training output.
3. It is fairly simple to add a program to just write to the knock-knock joke program database. I’ll post a version of this on the HitHub site. Is this machine learning? I would say, definitely! The machine has a capability that it did not have before.
4. play_wav_cmdline: paplay %1 --stream-name=mycroft-voice.

You can use this to play the audio...