QV refactor update & HGAP options

QV.[ch] module needed for QV support now core for all modules.

Option to only report overlaps when a-read is greater than a certain
size added.
MIT license

MIT license added to all files.
Potential out-of-block problems fixed in LAcat, split, merges, and sort.
Slight optimization to HGAP option for daligner
Merge remote-tracking branch 'upstream/master'
relax the condition for proper overlapping
the original one is too strigent for error correction
add experimental code for reducing data sizes