Merge remote-tracking branch 'qatar/release/0.5' into release/0.5

* qatar/release/0.5:
  Bump version number for 0.5.6 release.
  svq1dec: call avcodec_set_dimensions() after dimensions changed.
  vmd: fix segfaults on corruped streams
  vp6: partially propagate huffman tree building errors during coeff model parsing and fix misspelling
  Plug some memory leaks in the VP6 decoder
  vp6: Reset the internal state when aborting key frames header parsing
  vp6: Fix illegal read.
  vp6: Fix illegal read.
  Fix out of bound reads in the QDM2 decoder.
  Check for out of bound writes in the QDM2 decoder.
  qdm2: check output buffer size before decoding
  Fix qdm2 decoder packet handling to match the api


Merged-by: Michael Niedermayer <>