docs: Remove the Todo.md file

The Todo.md file has gotten stale, and it is no longer an effective
mechanism for tracking changes.  Remove it.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

docs/Overview.md

@@ -39,5 +39,3 @@ commands implemented in the micro-controller software.
 
 See [debugging](Debugging.md) for information on how to test and debug
 Klipper.
-
-See [todo](Todo.md) for information on possible future code features.

docs/Todo.md

@@ -1,71 +0,0 @@
-There are several features still to be implemented in Klipper. In no
-particular order:
-
-Host user interaction
-=====================
-
-* See if there is a better way to report errors. Octoprint sometimes
-  doesn't highlight an error (one has to look in the terminal tab to
-  find the error) and errors written to the log can be non-obvious to
-  a user.
-
-* Improve gcode interface:
-
- * Provide a way to temporarily disable endstop checks so that a user
-   can issue commands that potentially move the head past
-   position_min/position_max.
-
-* Improve logging:
-
- * Possibly collate and report the statistics messages in the log in a
-   more friendly way.
-
-* Possibly support a mechanism for the host to limit maximum velocity
-  so that the mcu is never requested to step at a higher rate than it
-  can support.
-
-Safety features
-===============
-
-* Support loading a valid step range into the micro-controller
-  software after homing. This would provide a sanity check in the
-  micro-controller that would reduce the risk of the host commanding a
-  stepper motor past its valid step range. To maintain high
-  efficiency, the micro-controller would only need to check
-  periodically (eg, every 100ms) that the stepper is in range.
-
- * Possibly support periodically querying the endstop switches and use
-   multiple step ranges depending on the switch state. This would
-   enable runtime endstop detection. (However, it's unclear if runtime
-   endstop detection is a good idea because of spurious signals caused
-   by electrical noise.)
-
-Testing features
-================
-
-* Complete the host based simulator. It's possible to compile the
-  micro-controller for a "host simulator", but that simulator doesn't
-  do anything currently. It would be useful to expand the code to
-  support more error checks, kinematic simulations, and improved
-  logging.
-
-Documentation
-=============
-
-* Add documentation describing how to perform bed-leveling accurately
-  in Klipper. Improve description of stepper phase based bed leveling.
-
-Hardware features
-=================
-
-* Support for additional kinematics: scara, etc.
-
-Misc features
-=============
-
-* Possibly support a "feed forward PID" that takes into account the
-  amount of plastic being extruded. If the extrude rate changes
-  significantly during a print it can cause heating bumps that the PID
-  overcompensates for. The temperature change due to the extrusion
-  rate could be modeled to eliminate these bumps and make the
-  extrusion temperature more consistent.