[commands] Update Command documentation (NFC) (#3881)

Add reference to which VendorDep the class is included in.
Add missing OldCommands C++ Documentation (copied from Java).

wpilibNewCommands/src/main/native/include/frc2/command/TrapezoidProfileSubsystem.h

@@ -14,6 +14,8 @@ namespace frc2 {
  * A subsystem that generates and runs trapezoidal motion profiles
  * automatically.  The user specifies how to use the current state of the motion
  * profile by overriding the `UseState` method.
+ *
+ * This class is provided by the NewCommands VendorDep
  */
 template <class Distance>
 class TrapezoidProfileSubsystem : public SubsystemBase {