The option dropdown for audio device selection lists all audio
device names. Dropdowns, however, may not have multiple identical
keys. This commit adds removal of duplicate audio device names from
the dropdown. BASS does not give us a simple mechanism to select
specific audio devices in such a case anyways. This functionality would
require OS-specific and involved code.
This commit hooks up AudioDevicesOptions to the new events exposed by
the AudioManager of osu-framework. The device list is now updated when
new devices become available or are lost.
Changed the name of the option for using the default audio device
to "Default" for consistency with english windows. Also changed
the "" value to string.Empty for consistency with the Frameworks
treatment of this special value.
