fixes serious typo
fixes wrong lookup on singleton intervals
simplify variables
removes some redundant checks
simplifies condition
more use of FVC
further simplifications
removes further needless checks
adds link to paper
reduces memory usage

The reverse-complement+forward string is only needed for the subjects in a comparison. Thus it can be computed on demand and freed afterwards. This reduces the memory from 3 byte per input nucleotide to 1+e where e depends on the number of threads.
stop failing on very similar sequences
updates citation
minor cleanup
Revert "more use of FVC"

This reverts commit 71218a5da1b1540165ac7081edc130d9201ceaf2.
Merge branch 'microopt'
updates kseq.h
more micro optimizations
updates man page
release v0.8
Merge branch 'master' into ubuntu