All data is now read from repository, so remove imports for direct reading.
Tidy code and activate plotting window at startup.
Put signal read/plot data code into the one function.
Connect to, and get recording data from, a BioSignalML repository.
Default to show all of recording if no start/duration is given (and if no duration, then show from start to end).
Use a 'main()' outer function.
Correctly refer to the recording URI.
Small code tweaks.
Keep the open polygon of the signal trace instead of a list of points and, if available, use C speedup code to create the polygon from numpy arrays.
Use a thread per signal for reading data.