*Structure_threader* is not parsing correctlly the results of STRUCTURE when there is a missing `extraparams` file

[StuntsPT]

Here is a snippet of the part the needs to be correctly parsed:

Inferred ancestry of individuals:
        Label (%Miss) :  Inferred clusters
  1 JW313_and_J    (0)   :  0.050 0.731 0.219 
  2 JW314_and_J    (0)   :  0.068 0.751 0.181 
  3 JW316_and_J    (2)   :  0.031 0.718 0.250 
  4 JW320_and_J    (0)   :  0.086 0.736 0.178 
  5    JW343    (0)   :  0.200 0.723 0.077 
  6    JW344    (0)   :  0.141 0.784 0.075 
  7    JW439    (0)   :  0.092 0.758 0.150 
  8    JW638    (0)   :  0.098 0.771 0.131 
  9    JW639    (0)   :  0.114 0.768 0.118 
 10    JW645    (0)   :  0.061 0.731 0.208 
 11 JW646_and_J    (0)   :  0.064 0.723 0.214 
 12 JW648_and_J    (0)   :  0.099 0.731 0.170 
 13    JW654    (5)   :  0.264 0.679 0.056 
 14    JW655    (0)   :  0.155 0.755 0.090 
 15 JW656_and_J    (1)   :  0.056 0.791 0.152 
 16    JW659    (0)   :  0.161 0.731 0.108 
 17 JW660_and_J    (1)   :  0.180 0.732 0.088 
 18    JW661    (0)   :  0.143 0.740 0.116 
 19    JW663    (0)   :  0.079 0.712 0.209 
 20    JW664    (0)   :  0.146 0.741 0.112 
 21    JW924    (0)   :  0.156 0.735 0.109 

(Yes, in this variant there are no separators like in the other variants.)

[StuntsPT]

Fixed via 964339d7b36c2e9add76a19f438b81e87a6f4011.