add authors and description to README

README.md

 # PopSimul
 
+## Authors
+Cécile Triay (IRD)
+Alice Boizet (CIRAD)
+Mathias Lorieux (IRD)
+Mathieu Triay (Atelier Triay)
+
 ## Description
+This tool enables to simulate a VCF of a bi-parental population. It can be used to produce a VCF under controlled conditions with setting parameters such as average depth, marker density and expected error rate. It produces 2 VCF files with the simulated genotypes, one with simulated data, and one with the same simulated data but with simulated genotyping errors. 
+The Breakpoints csv file contains the positions of exact genotypes transitions based on the simulated data. This tool has been used to test NOISYmputer (https://gitlab.cirad.fr/noisymputer/noisymputerstandalone) to compare exact Breakpoints position to Breakpoints positions determined on imputed data.
 
 ## Requirements
 python 3
@@ -25,3 +33,5 @@ You can see all parameters by running this command
 | -m  | --max_depth | max depth | 10 |
 | -eA | --error_rate_A | error rate for A | 0.05 |
 | -eB | --error_rate_B | error rate for B | 0.05 |
+
+