Save output from demos into a log file

_This is one of the ideas for future development I have. No final assignment yet, just a subject to talk about it and possibly bring some good ideas together. I am looking forward to hear your feedback or thoughts._

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Right now, when the demos are executed, they print something to the standard output of the terminal where the Java app runs. The output is flooded with text as the number of JEPs is growing.

Would be good to have some text file (by default in `/tmp`, later it might be a configurable path of user's preference) where we would copy the output, so it is stored for the user for future reference.