"No duration"-situations are covered, video title displayed in controller

The duration/remaining Timecode will not be rendered and the progress bar will be rendered as disabled.
Improved title display, added prev/next file buttons, fixed bar for "out of bound" chapters

The title-text will now be scaled horizontally if it is longer than 85 chracters to (hopefully) prevent it from glitching.

Buttons to go the the previous/next playlist entry where added.

The bar won't render chapters that are behind duration anymore.
Merge remote-tracking branch 'remotes/origin/lua_experiment' into lua_experiment

Conflicts:
	osc.lua
Time now uses ratio-pos, title scale over 80 chars
Seekbar now seeks with absolute-percent
command: add properties to retrieve playlist position/count

Maybe playlist-pos should be writeable (could get rid of the
playlist_next/_prev commands too), but let's leave that for later.