data which wasn't initialized when the init code was compiled out.

* use av_audio_resample_init
* new option to output information about files as json array

track audio and video eos separately so they are closer to each other if -s / -e is used to cut out segments

  if seeking between keyframes

  Only text (raw UTF-8 and SSA) is supported.
  SSA tags are not properly removed yet.
* update libkate to 0.3.1

use vstream.time_base if it those values are in range, use r_frame_rate otherwise, fixes issues with some mp4 files that list field and not frame rate in the later

- disable vhooks for now, not working with ffmpeg trunk
- store and use visble height/width before initializing decoder.
  this removes green borders for some flv vp6 files.