Update README with installation instructions

Author: Aarthi Venkat

README.md

@@ -1 +1,10 @@
-Codebase for "Beta cells are essential drivers of pancreatic ductal adenocarcinoma development"
+# Codebase for "Beta cells are essential drivers of pancreatic ductal adenocarcinoma development"
+
+### System requirements
+Python 3.8.18 on any operating system with no non-standard software required.
+
+### Installation guide (typical installation time: ~5-10 minutes)
+Install graphtools 1.5.3, tensorflow 2.13.0, keras 2.13.1, numpy 1.22.4, scikit-learn 1.3.2, scipy 1.10.1, tqdm 4.66.4, scanpy 1.9.3, phate 1.0.11, magic 3.0.0, TrajectoryNet 0.2.4, scMMGAN 0.0
+
+### Instructions for use
+Each folder contains Python scripts and notebooks pertaining to analysis related to each figure for reproducibility. Small data files, figures, and results files included, and large data files available upon request.