[robotpy][examples] Split examples and snippets (#8944)

This also updates the bazel scripts to behave more like the C++ and Java
examples, and updates the copybara scripts to be able to sync up
`mostrobotpy`

robotpyExamples/snippets/MotorControl/robot.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) FIRST and other WPILib contributors.
+# Open Source Software; you can modify and/or share it under the terms of
+# the WPILib BSD license file in the root directory of this project.
+#
+
+import wpilib
+
+import math
+
+
+class MyRobot(wpilib.TimedRobot):
+    """
+    This sample program shows how to control a motor using a joystick. In the operator control part
+    of the program, the joystick is read and the value is written to the motor.
+
+    Joystick analog values range from -1 to 1 and motor controller inputs also range from -1 to 1
+    making it easy to work together.
+
+    In addition, the encoder value of an encoder connected to ports 0 and 1 is consistently sent
+    to the Dashboard.
+
+    Finally, short code snippets show how to invert the motor direction and how to use the motor
+    safety for frc-docs.
+    https://docs.wpilib.org/en/stable/docs/software/hardware-apis/motors/wpi-drive-classes.html
+    """
+
+    kMotorPort = 0
+    kJoystickPort = 0
+    kEncoderPortA = 0
+    kEncoderPortB = 1
+
+    def __init__(self):
+        """Robot initialization function"""
+        super().__init__()
+
+        self.motor = wpilib.PWMSparkMax(self.kMotorPort)
+        self.joystick = wpilib.Joystick(self.kJoystickPort)
+        self.encoder = wpilib.Encoder(self.kEncoderPortA, self.kEncoderPortB)
+        # Use SetDistancePerPulse to set the multiplier for GetDistance
+        # This is set up assuming a 6 inch wheel with a 360 CPR encoder.
+        self.encoder.setDistancePerPulse((math.pi * 6) / 360.0)
+
+        # show motor inversion
+        self.motor.setInverted(True)
+
+        # show motor safety features
+        self.motor.setSafetyEnabled(True)
+        self.motor.setSafetyEnabled(False)
+        self.motor.setExpiration(0.1)
+        self.motor.feed()
+
+    def robotPeriodic(self):
+        """The RobotPeriodic function is called every control packet no matter the robot mode."""
+        wpilib.SmartDashboard.putNumber("Encoder", self.encoder.getDistance())
+
+    def teleopPeriodic(self):
+        self.motor.setThrottle(self.joystick.getY())