plot for segments of continuous
extracted function read_dir to signal_processing.utils, now
continuous.io.read_wav_many is nicer
added TODO to segments of continuous from file
encapsulated also write_dir to utils
default parameter params in utils.read_dir
utils.is_close_many for tests
easier testing of continuous.io using utils
fixed imports, implemented segs_to_dir, segs_from_dir
tests working