Chimeric splitting fix

A small update with edge case checks for trimming with middle adapter checks.

Paired Barcodes

Demultiplexing via the trim command can now filter reads to those with matching front/back adapters.

Demultiplexing

Enabling basic demultiplexing of barcoded sequences.

Overlap quick fix

Overlap now correctly uses the new approach developed for the map command.
This resolves a hard crash and gets performance back to reasonable levels.

Version 0.3

Added command for reference-based mapping.
Optimisations for seed-based matching (should help overlap too).
Added subseq command for fast sequence retrieval on the command-line.

Verion 0.2

Added the overlap command.
Moved to packed byte sequences.
Now dependent on amd64 platform, basic SSE.
downpore.gz

Trim only, high memory edition

v0.1.1

Added version command. Extended trim comparison table.

Version 0.1, trim only

v0.1

Version 0.1 trim only