merge r199 changes; part 1
merge r199 changes; part 2
merge r199 changes; part 3
added bam2bed
r198: tag version
r199: reduce one conflict when merged with master
r200: the previous is not good enough
Exported some routines
Allow to skip errors
Append new header lines
added this missing file
Merge branch 'lite'

Conflicts:
	Makefile
	htslib/hts.h
	htslib/tbx.c
	htslib/vcf.c
	htslib/vcf.h
	main.c