Moved C++ comments from source files to headers (#1111)

Also sorted functions in C++ sources to match order in related headers.

wpilibc/src/main/native/include/Drive/RobotDriveBase.h

@@ -44,9 +44,32 @@ class RobotDriveBase : public MotorSafety, public SendableBase {
   RobotDriveBase(const RobotDriveBase&) = delete;
   RobotDriveBase& operator=(const RobotDriveBase&) = delete;
 
+  /**
+   * Sets the deadband applied to the drive inputs (e.g., joystick values).
+   *
+   * The default value is 0.02. Inputs smaller than the deadband are set to 0.0
+   * while inputs larger than the deadband are scaled from 0.0 to 1.0. See
+   * ApplyDeadband().
+   *
+   * @param deadband The deadband to set.
+   */
   void SetDeadband(double deadband);
+
+  /**
+   * Configure the scaling factor for using RobotDrive with motor controllers in
+   * a mode other than PercentVbus or to limit the maximum output.
+   *
+   * @param maxOutput Multiplied with the output percentage computed by the
+   *                  drive functions.
+   */
   void SetMaxOutput(double maxOutput);
 
+  /**
+   * Feed the motor safety object. Resets the timer that will stop the motors if
+   * it completes.
+   *
+   * @see MotorSafetyHelper::Feed()
+   */
   void FeedWatchdog();
 
   void SetExpiration(double timeout) override;
@@ -58,8 +81,24 @@ class RobotDriveBase : public MotorSafety, public SendableBase {
   void GetDescription(wpi::raw_ostream& desc) const override = 0;
 
  protected:
+  /**
+   * Limit motor values to the -1.0 to +1.0 range.
+   */
   double Limit(double number);
+
+  /**
+   * Returns 0.0 if the given value is within the specified range around zero.
+   * The remaining range between the deadband and 1.0 is scaled from 0.0 to 1.0.
+   *
+   * @param value    value to clip
+   * @param deadband range around zero
+   */
   double ApplyDeadband(double number, double deadband);
+
+  /**
+   * Normalize all wheel speeds if the magnitude of any wheel is greater than
+   * 1.0.
+   */
   void Normalize(wpi::MutableArrayRef<double> wheelSpeeds);
 
   double m_deadband = 0.02;