Updated LAV Filters to 0.63-23-c4208b1 (custom build based on 0.63-17-881d809).

Important changes:
 - LAV Video Decoder: Fix a crash related to DVD subs (fixes #5522) (regression from 73d3cab944635944d6d0034376c743798ee5bdd8).
 - LAV Audio Decoder: Fix a possible crash when seeking (fixes #5523) (regression from 73d3cab944635944d6d0034376c743798ee5bdd8).
 - LAV Audio Decoder: Switch to native FFmpeg decoder for Opus.
 - Update FFmpeg library.
Update AStyle to v2.05.

Workaround some regressions while at it...
(WIP/Broken) Disable the time tooltip shadow for incompatible video renderers.

Some video renderers cause the tooltip shadow to be replaced by an opaque black box.

Fixes #1415.
(WIP/Broken) Try to find out if VMR-7 uses overlays, without luck so far...
Don't force any background color for the Shockwave graph.

This commit fixes #1747.
WebUI: Inform the web interface that no audio stream is available.
WebUI: Make use of new [hasaudio] info.
What the hell was intended here?!

Trying to make some sense of that code. Without much luck so far...