[WIP] Enable banding for computing k-mer abundance distributions

[standage]

Banding stuff has been pretty well battle tested in kevlar, but hasn't made it to the khmer CLI yet. This requires not only adding arguments to support banding, but integrating *table objects into the tooling originally designed only for *graph objects.

• Is it mergeable?
• make test Did it pass the tests?
• make clean diff-cover If it introduces new functionality in
  scripts/ is it tested?
• make format diff_pylint_report cppcheck doc pydocstyle Is it well
  formatted?
• Did it change the command-line interface? Only backwards-compatible
  additions are allowed without a major version increment. Changing file
  formats also requires a major version number increment.
• For substantial changes or changes to the command-line interface, is it
  documented in CHANGELOG.md? See keepachangelog
  for more details.
• Was a spellchecker run on the source code and documentation after
  changes were made?
• Do the changes respect streaming IO? (Are they
  tested for streaming IO?)

[standage]

This depends on consume_seqfile_banding_with_reads_parser from #1753.

[standage]

Some initial benchmarking this weekend: ran abund-dist-single.py with & without banding (--banding 8 1) and with & without threading (--threads 4). Banding does provide a runtime performance improvement, but it appears that the improvement doesn't stack with improvements from threading.

[standage]

Hmm. The cyclic hash is not only faster than the murmur hash (we already knew that), but its speed benefits seem to stack better with threading. The commands I used:

time scripts/abundance-dist-single.py --hash-function cyclic --max-memory-usage 25M --ksize 25 ~/Desktop/kevlar/scratch/nano-trio/proband-reads.fq.gz nobanding-nothreads.abunddist
time scripts/abundance-dist-single.py --hash-function cyclic --banding 8 1 --max-memory-usage 25M --ksize 25 ~/Desktop/kevlar/scratch/nano-trio/proband-reads.fq.gz banding-nothreads.abunddist
time scripts/abundance-dist-single.py --hash-function cyclic --threads 4 --max-memory-usage 25M --ksize 25 ~/Desktop/kevlar/scratch/nano-trio/proband-reads.fq.gz nobanding-threads.abunddist
time scripts/abundance-dist-single.py --hash-function cyclic --threads 4 --banding 8 1 --max-memory-usage 25M --ksize 25 ~/Desktop/kevlar/scratch/nano-trio/proband-reads.fq.gz banding-threads.abunddist