Improve performance of inverse DWT 5x3 (#953)

Improve performance of inverse DWT 5x3 (#953)

* Use single-pass lifting inverse wavelet transform.
* For vertical pass, use SSE2 when available so as to process 8 columns
  in parallel. This is the most beneficial improvement, since the
  vertical pass involves a lot of cache trashing.

With the bench_dwt utility with default arguments (16383x16383 image),
time goes from 4.064 s to 1.212 s.