vignette update

vignettes/GenomeFeatures.Rmd

@@ -43,7 +43,7 @@ At the first step we read peaks files (also known bed files with genomic coordin
 ```{r peaks}
 ###################
 # load peak files 
-peaks=base::list(
+peaks=GenomicRanges::GRangesList(
   A=GenomeFeatures::readPeakFile(
    base::system.file(
      "extdata/data/input/A.bed",