add note about single-end
add note about single-end

brentp/bwa-meth,dariober/bwa-meth,PeteHaitch/bwa-parclip,brentp/bwa-meth,dariober/bwa-meth,brentp/bwa-meth,dariober/bwa-meth,PeteHaitch/bwa-parclip,PeteHaitch/bwa-parclip