initial function management refactoring

TODO.md

@@ -1,18 +1,18 @@
 ## TODO:
-1. Multiple functions in one graph.
-	- Backend support
-		- Integrals between functions (too hard to implement, maybe will shelve)
-		- Display intersection between functions (would have to rewrite a lot of the function plotting handling)
-2. Rerwite of function parsing code
-	- Non `y=` functions.
-3. Smart display of graph
+1. Function management
+	- Integrals between functions (too hard to implement, maybe will shelve)
+	- Display intersection between functions (would have to rewrite a lot of the function plotting handling)
+	- Sort by UUIDs
+	- [Drag and drop support](https://github.com/emilk/egui/discussions/1530) in the UI
+	- Hide/disable functions
+2. Smart display of graph
 	- Display of intersections between functions
-4. Allow constants in min/max integral input (like pi or euler's number)
-5. Sliding values for functions (like a user-interactable slider that adjusts a variable in the function, like desmos)
-6. Fix integral display
-7. Better handling of panics and errors to display to the user
-8. Turn Dynamic Iterator functions into traits
-9. Better handling of roots and extrema finding
-10. Add closing animation for function entry
-11. Create actual icon(s) for PWA/favicon (using placeholder from eframe_template)
-12. Fix mobile text input
+3. Allow constants in min/max integral input (like pi or euler's number)
+4. Sliding values for functions (like a user-interactable slider that adjusts a variable in the function, like desmos)
+5. Fix integral display
+6. Better handling of panics and errors to display to the user
+7. Turn Dynamic Iterator functions into traits
+8. Better handling of roots and extrema finding
+9. Add closing animation for function entry
+10. Create actual icon(s) for PWA/favicon (using placeholder from eframe_template)
+11. Fix mobile text input