Updates all print statements to python 3 style prints.
Adds message when trying to send non printable ASCII characters.
Adds screenshot and displays it in readme.
Removes unused capture audio helper.
Revert "Removes unused capture audio helper."

This reverts commit 2996177950985a96e4fb4c4179cd43bd6ea53f6c.
Actually we do need capture_audio.py, but only for the notebooks.
Fixes buffer overrun issue construidor found and corrected.
Fixes audible squawking by not having any jumps in phase. Also cleans up envelope function.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	quietnet.py
	send.py