added todos in readme.md

Author: shayan15sa

README.md

@@ -2,3 +2,8 @@
 A gravity system simulator in go with raylib bindings
 
 I'm open to any PR
+
+## TODOS
+- [ ] Implementing an interface for adding planets with the GUI
+- [ ] Adding releases for win linux mac with github action
+- [ ] Separating the logic in a different file (module?)