Handle selection of audio devices that don't have (enough) input or output channels #7
Description
At the moment it can happen that the default audio device (id 0) does not have any output channels, which, unless handled manually, causes the library initialisation to fail with an obscure error message (see https://discourse.processing.org/t/weird-out-of-bounds-issue-with-the-sound-library/2810/4 and https://discourse.processing.org/t/sound-error-when-trying-to-construct-any-object/3283/4).
Default input and output device selection should be improved to select the first available device that actually has input/output channels, along with some error handling when the user manually selects an inappropriate device (see https://discourse.processing.org/t/outputdevice-in-sound-library-causing-errors-when-specifying-audio-channel/3222/6).