Avoid bare try-except

[dhalbert]

A number of examples here have code like:

try:
    # something that might fail
except:
    return # or pass or something like that

Sometimes there's good reason for a "bare except", but a lot of times it could hide an unexpected error. It's better to list the expected exceptions explicitly [how's that for alliteration?]. An example is:

Adafruit_Learning_System_Guides/Hallowing_Lightsaber/lightsaber_standard.py

Lines 52 to 57 in 4879082

	try:
	wave_file = open('sounds/' + name + '.wav', 'rb')
	wave = audioio.WaveFile(wave_file)
	AUDIO.play(wave, loop=loop)
	except:
	return

.

I think this might have meant to catch missing audio files, but it started catching audioio.WaveFile() failure (because now it's audiocore.WaveFile().) and not complaining. This made the failure non-obvious to an experienced user in the forums.