Rockbox

This patch adds an option to allow the Fastforward/Rewind buttons to be used to skip tracks entirely.

This is an itch of mine that I scratched and am offering up to others if you are interested.

I've been using audio lessons to learn Japanese and ran into issues navigating with the normal FF/RW buttons. The acceleration based on track length left me with no sense of time since I don't keep track of how far I am into my 30 minute long lessons. Simply backing up 5 seconds to catch something I missed was a problem because I'd have to look at what I was doing to see how far I'd ff/rw. Kinda hard when one tick moves 30 seconds too. This is problematic when driving! The existing skip-length feature is really good for this. However, if I use that to skip 5 second increments then I abandon any way of skipping entire tracks. So I re-purposed the FF/RW buttons for skipping tracks and use skip-length for navigating within a track.

I've been using this in r27841 for about a week on my Gigabeat, but it seems like it should work for r27942 as well.

 apps/gui/wps.c       |  260 ++++++++++++++++++++++++++++-----------------------
 apps/settings_list.c |    7 -
 2 files changed, 149 insertions(+), 118 deletions(-)