Update README.md

add authors

Author: sarah-ji

README.md

@@ -1,6 +1,8 @@
 # QuasiCopula.jl
 A Flexible Quasi-Copula Distribution for Statistical Modeling
 
+Authors: Sarah Ji, Kenneth Lange, Hua Zhou, Janet Sinsheimer, Benjamin Chu
+
 | **Documentation** | **Build Status** | **Code Coverage**  |
 |-------------------|------------------|--------------------|
 | [![](https://img.shields.io/badge/docs-dev-blue.svg)](https://OpenMendel.github.io/QuasiCopula.jl/dev) [![](https://img.shields.io/badge/docs-stable-blue.svg)](https://OpenMendel.github.io/QuasiCopula.jl/stable) | [![build Actions Status](https://github.com/OpenMendel/QuasiCopula.jl/workflows/CI/badge.svg)](https://github.com/OpenMendel/QuasiCopula.jl/actions) [![CI (Julia nightly)](https://github.com/openmendel/QuasiCopula.jl/workflows/JuliaNightly/badge.svg)](https://github.com/OpenMendel/QuasiCopula.jl/actions/workflows/JuliaNightly.yml)| [![codecov](https://codecov.io/gh/OpenMendel/QuasiCopula.jl/branch/master/graph/badge.svg?token=YyPqiFpIM1)](https://codecov.io/gh/OpenMendel/QuasiCopula.jl) |