Keeping track of audio markers and labels to be shown in the audio
display is not particularly related to AudioController's primary
responsiblity of controlling the playback of audio.
Originally committed to SVN as r6427.
The sample rate of the currently open audio is not something that things
which do not interact with the raw audio data should have to care about,
or even know about.
Originally committed to SVN as r6426.
Move most karaoke parsing/serializing/editing code to AssKaraoke rather
than being scattered all over the place, and add much better support for
non-karaoke override tags and comments.
Add a karaoke timing controller.
Redesign the karaoke syllable split/join interface to have a single mode
from which both splitting and joining can be done rather than separate
split and join modes.
Only show the karaoke split/join bar when karaoke mode is enabled.
Closes#886, #987, #1190.
Originally committed to SVN as r5613.
