Command Scheduler should keep track of execution time deltas

[SomewhatMay]

If the command scheduler encounters unnecessarily long asynchronous yields (within Command::execute or Subsystem::periodic), it should warn the user of the issue immediately.

[SomewhatMay]

Expand debugging and state information to be visible on the pros::lcd::display as well as on the controller display

[vaddikeshavareddy]

Implement a timeout threshold within the scheduler to flag and log excessive asynchronous yield durations.

[SomewhatMay]

The uvlib command scheduler will take ownership of line 0 on the Robot's brain and line 0 of the controller. It will use these to display status information.

[SomewhatMay]

take ownership of line 0 on the Robot's brain

As a result, make sure to initialize the pros::lcd!

[SomewhatMay]

This needs to be heavily tested before closing the issue! Also we must remember to state the following in the documentation/README.md:

The uvlib command scheduler will take ownership of line 0 on the Robot's brain and line 0 of the controller. It will use these to display status information.

...make sure to initialize the pros::lcd!