Merge commit '3e265ca58f0505470186dce300ab66a6eac3978e'

* commit '3e265ca58f0505470186dce300ab66a6eac3978e':
  avconv: do packet ts rescaling in write_packet()

This commit is a noop since it doesn't apply cleanly due to differences
in the dataflow between avconv and ffmpeg, and thus fixing this in the
scope of a merge is unfeasible.

Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>