save raw feature start and end
start and end feature
don't compress bam output when its being piped into mpileup
create temp files in the current directory, not in /tmp
Merge pull request #37 from andrewjpage/more_speedup

Create tmp files in cwd not /tmp
random seed after fork to avoid tmp file name clash
Merge pull request #38 from andrewjpage/more_speedup

random seed after fork to avoid tmp file name clash