fixed typo in qlen __get__
fixed typo in qlen __get__

carolinux/pysam,kyleabeauchamp/pysam,pysam-developers/pysam,dannon/pysam,brendanofallon/pysam,daler/pysam,brendanofallon/pysam,daler/pysam,brendanofallon/pysam,mattions/pysam,brendanofallon/pysam,dannon/pysam,bioinformed/pysam,pysam-developers/pysam,TyberiusPrime/pysam,nlhepler/pysam,mattions/pysam,carolinux/pysam,daler/pysam,bioinformed/pysam,kyleabeauchamp/pysam,bioinformed/pysam,pysam-developers/pysam,TyberiusPrime/pysam,bioinformed/pysam,bioinformed/pysam,nlhepler/pysam,dannon/pysam,mattions/pysam,dannon/pysam,daler/pysam,nlhepler/pysam,brendanofallon/pysam,nlhepler/pysam,carolinux/pysam,nlhepler/pysam,daler/pysam,mattions/pysam,carolinux/pysam,dannon/pysam,kyleabeauchamp/pysam,kyleabeauchamp/pysam,TyberiusPrime/pysam,TyberiusPrime/pysam,pysam-developers/pysam,carolinux/pysam,mattions/pysam,kyleabeauchamp/pysam,TyberiusPrime/pysam