Introduce two new audio filters to handle generation, detection and decoding of Baudot tones. Also introduce, encoding and decoding contexts, on which the new filters rely to handle the encoding and decoding of the text transmitted with Baudot tones. Add a new AUDIO_STREAM_FEATURE_BAUDOT, to be able to activate/deactivate the Baudot feature. Add new functions on the AudioStream, to configure the two new Baudot audio filters and enable sending of text in the AudioStream via Baudot tones. Add new tests to check that this newly added functionality is working as expected.