configure: include dependency libs in the Libs pkg-config

If only a static library is built, the user of the library that just
tries to link to the lib using the flags provided by pkg-config
might not know that only a static lib exists and that he'd have to
pass --static to pkg-config to get the internal dependencies to
be able to link the library.

For a shared build, the internal dependencies are kept in Libs.private
as before.

This matches how libav's pkg-config files are generated.
configure: don't generate a git version number if .git isn't present
version.sh: change to use /bin/sh
Update to current libav/ffmpeg API
Replace gf_malloc with regular malloc in mp4 muxer

It was used as a workaround for a bug that only existed in the GPAC repository
for a few weeks back in 2010. There's no reason to keep it anymore.
Use calloc instead of malloc + memset
x86inc: Make ym# behave the same way as xm#

This makes more sense for future implementations of templates with zmm registers.
CRF-max: don't warn if VBV underflow occurs

Only warn if underflow occurs for reasons other than CRF-max, as CRF-max
implies that VBV underflow is desired by the user.
chroma-me: take shortcut in BI analysis

~100 cycles faster with subme>=9
Make x264_encoder_reconfig more threadsafe

Do the reconfig when the next frame's encode begins.
Fixes some rare crashes with frame-threading and encoder_reconfig.
Add --filler option

Allows generation of hard-CBR streams without using NAL HRD.
Useful if you want to be able to reconfigure the bitrate (which you can't do
with NAL HRD on).
Add AVC-Intra 1080p50/60 Class 100 parameters

Also add some compatibility fixes.
Add L-SMASH support as preferable alternative for MP4-muxing
Remove --visualize option.

It probably wasn't used or maintained for last few years.
Fix uninitialized variable

Caused if the timebase is not specified in stats file. Found by Clang.
Fix ARM asm compilation with Apple assembler
Fix input support from named pipes in Windows