Ajout de outSAMattrRGline cf : http://labshare.cshl.edu/shares/gingeraslab/www-data/dobin/STAR/STAR.posix/doc/STARmanual.pdf 

> string(s):  SAM/BAM read group line.  The first word contains the read groupidentifier and must start with ”ID:”, e.g.  –outSAMattrRGline ID:xxx CN:yy”DS:z z z”.xxx will be added as RG tag to each output alignment.  Any spaces in the tagvalues have to be double quoted

added volcano plots to report, changed heatmap of DEG from full samples to samples only included in comparison