resample: fix avresample_get_delay() return value

The correct "next" input sample is not the first sample of the
resampling buffer, but the center sample of the filter_length-sized
block at the beginning.

CC:libav-stable@libav.org
resample: split the nearest neighbour path into a separate function pointer
resample: reindent
resample: drop useless abs()

negative sample_index is handled in the block above.
resample: add initial padding explicitly

This simplifies the code, since we do not have to deal with a possibly
negative source index anymore.
resample: split linear into its own function
Merge commit 'b9dea23766f52b8e059e72d34980bb7b456efe8f'

* commit 'b9dea23766f52b8e059e72d34980bb7b456efe8f':
  resample: fix avresample_get_delay() return value

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'f20892eb67a7b4b5a3c080388a35a3380516a805'

* commit 'f20892eb67a7b4b5a3c080388a35a3380516a805':
  resample: split the nearest neighbour path into a separate function pointer

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '3c84f6b5d20cd345fac706f8cfb70c55e541ffb5'

* commit '3c84f6b5d20cd345fac706f8cfb70c55e541ffb5':
  resample: reindent

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'eed752d61da332fb13e9893a175a90fed7b1d7d3'

* commit 'eed752d61da332fb13e9893a175a90fed7b1d7d3':
  resample: drop useless abs()

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'be394968c81019887ef996a78a526bdd85d1e216'

* commit 'be394968c81019887ef996a78a526bdd85d1e216':
  resample: add initial padding explicitly

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '254c95cdd1b669a722204a4a65974fc2523c8f83'

* commit '254c95cdd1b669a722204a4a65974fc2523c8f83':
  resample: split linear into its own function

Merged-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/jpegls: print coding parameters stored in LSE

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>