Adjusted the way key sounds are obtained (for the demo).

Limited sounds added for demo keyboard (IBM SSK).
Reverted to having a single, key-capture callback.
Merge branch 'master' of https://github.com/cpoliver/KeySounds

Conflicts:
	KeySounds.KeyboardManagement/KeySounds.KeyboardManagement.csproj
	KeySounds.KeyboardManagement/Model/KeyboardManager.cs
	KeySounds.KeyboardManagement/Modules/model m/keyboard.json