threshold as percent/fraction rather than read number

[rjsorr]

Pleae add an option for -t (threshold) as perecent/fraction instead of read number. read number i only useful if all datasets are the same size, which they aren't. For example 0.01% (0.0001) 0.005% (0.00005), or 0.003% (0.00003), or a user defined value.