Audio support

And some other old l-smash base functions
1. configure: Add --disable-* option for audio encoders
2. always use strict=-2 for aac
3. assume channels = 2 when can't get them
4. Skip useless lavr check when lavf is not available
5. Add --chpl-with-bom option
Add an option to use r2204 style progress indicator
Add back "touhou" tune
Utilize internal threading in lavf/ffms
Auto VBV settings
Log file
Encoding time
Level force
Profile force
Print video info with lavf/ffms demuxer
AviSynth 16bit hack
Skip bit depth filter when possible
Use f3kdb for bit depth conversion when needed

This fixes high bit depth AviSynth input with input-depth != 16 or BIT_DEPTH
Detect color matrix with lavf/ffms demuxer
Fix AviSynth color space converting matrix
Fix swscale color space converting matrix
Support "dgi" file extension
Support "vpy" file extension
Support invoking LSMASHSource in avs demuxer
Variable progress precision, print encoded file size & estimated total size

This patch may cause progress indicator to exceed console width limit.
Try to increase width of console window to avoid the problem.