[wpilib] Make drive classes follow NWU axes convention (#4079)

All trigonometric functions and vector classes assume North-West-Up axes
convention, so using North-East-Down convention with them is really
error-prone. We've broken something every time we touched the drive
classes.

We originally used North-East-Down to match the joystick convention, but
the volume of long-lived bugs has made this not worth it in retrospect.

The rest of WPILib also uses North-West-Up, so this makes things
consistent.

KilloughDrive was removed since no one uses it.

wpilibcExamples/src/main/cpp/examples/MecanumControllerCommand/cpp/subsystems/DriveSubsystem.cpp

@@ -50,7 +50,7 @@ void DriveSubsystem::Periodic() {
 void DriveSubsystem::Drive(double xSpeed, double ySpeed, double rot,
                            bool fieldRelative) {
   if (fieldRelative) {
-    m_drive.DriveCartesian(ySpeed, xSpeed, rot, -m_gyro.GetAngle());
+    m_drive.DriveCartesian(ySpeed, xSpeed, rot, m_gyro.GetRotation2d());
   } else {
     m_drive.DriveCartesian(ySpeed, xSpeed, rot);
   }