Add TODO list to README

README.md

@@ -17,3 +17,11 @@ Input programs are specified as a list of CPU instructions. For a list of instru
 Once you have the program specified, call `gbso.optimize.optimize` on the program. A superoptimized, behaviorally equivalent program will be returned. Additional parameters are available to the optimization function to control search.
 
 For a comprehensive example, see [ex.py](./ex.py).
+
+## TODO
+
+- [ ] Cost penalties for undefined memory/register reads
+- [ ] "Improved" equality metric that accounts for correct results in the wrong location
+- [ ] Automatic test case generation from counterexamples
+- [ ] `DAA` instruction
+- [ ] 16-bit memory/register outputs