[wpilib,cmd] Cache HID wrappers (#8970)

Store DriverStation-owned GenericHID and Gamepad instances in Java and
C++, and expose the cached objects to Python bindings.

Move hand-written command gamepad and joystick wrappers to compose
cached CommandGenericHID instances plus typed HID wrappers, including a
Python CommandGamepad.

This will let us remove UserControls, while helping ensure that we don't
have state smashing between GenericHID objects.

Another bonus is without inheritance, intellisense will no longer show a
bunch of annoying methods, and instead just what actually exists.

---------

Co-authored-by: Peter Johnson <johnson.peter@gmail.com>

commandsv2/src/main/python/commands2/button/__init__.py

@@ -1,4 +1,5 @@
 from .commandgenerichid import CommandGenericHID
+from .commandgamepad import CommandGamepad
 from .commandjoystick import CommandJoystick
 from .commandnidsps4controller import CommandNiDsPS4Controller
 from .commandnidsxboxcontroller import CommandNiDsXboxController
@@ -10,6 +11,7 @@ from .trigger import Trigger
 __all__ = [
     "Trigger",
     "CommandGenericHID",
+    "CommandGamepad",
     "CommandJoystick",
     "CommandNiDsPS4Controller",
     "CommandNiDsXboxController",