esp32phone as a submodule

[sosaucily]

Hi! This is a cool project, I've seen enough people chatting about something like this online, so I'm happy to see you took it on. I'm interested in using this, and helping out a bit along the way as I can as well.

Would you be open to organizing this in such a way that the esp32phone / sipphone module could itself be a stand-along submodule that can be imported into a project? Then there would be a project like this, which included all the code to run and test the esp32baresip phone (an example of how to use it), and another module that people can actually import directly.

Thanks!