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
More detailed version head
Add an option to use r2204 style progress indicator
Add back "touhou" tune
Film Grain Optimization
Fade Compensation
Remove stats before renaming
Add a parameter to set level of writing options in User Data Unregistered SEI
Utilize internal threading in lavf/ffms
Auto VBV settings
AVI output
filters hqdn3d pad vflip yadif patch
Log file
Encoding time
Level force
Profile force
Cosmetic
New experimental AQ mode (modification of Auto-variance AQ)
Print video info with lavf/ffms demuxer
lto & Ofast