[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/I2CCommunication/robot.py

@@ -0,0 +1,54 @@
+#!/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
+
+
+class MyRobot(wpilib.TimedRobot):
+    """
+    This is a sample program demonstrating how to communicate to a light controller from the robot
+    code using the roboRIO's I2C port.
+    """
+
+    PORT = wpilib.I2C.Port.PORT_0
+    DEVICE_ADDRESS = 4
+
+    def __init__(self):
+        """Robot initialization function"""
+        super().__init__()
+
+        self.arduino = wpilib.I2C(self.PORT, self.DEVICE_ADDRESS)
+
+    def writeString(self, s: str):
+        # Creates a char array from the input string
+        chars = s.encode("ascii")
+
+        # Writes bytes over I2C
+        self.arduino.writeBulk(chars)
+
+    def robotPeriodic(self):
+        # Creates a string to hold current robot state information, including
+        # alliance, enabled state, operation mode, and match time. The message
+        # is sent in format "AEM###" where A is the alliance color, (R)ed or
+        # (B)lue, E is the enabled state, (E)nabled or (D)isabled, M is the
+        # operation mode, (A)utonomous or (T)eleop, and ### is the zero-padded
+        # time remaining in the match.
+        #
+        # For example, "RET043" would indicate that the robot is on the red
+        # alliance, enabled in teleop mode, with 43 seconds left in the match.
+        allianceString = "U"
+        alliance = wpilib.MatchState.getAlliance()
+        if alliance is not None:
+            allianceString = "R" if alliance == wpilib.Alliance.RED else "B"
+
+        enabledString = "E" if wpilib.RobotState.isEnabled() else "D"
+        autoString = "A" if wpilib.RobotState.isAutonomous() else "T"
+        matchTime = wpilib.MatchState.getMatchTime()
+
+        stateMessage = f"{allianceString}{enabledString}{autoString}{matchTime:03f}"
+
+        self.writeString(stateMessage)