[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/HttpCamera/robot.py

@@ -0,0 +1,20 @@
+#!/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 wpilib.cameraserver
+
+
+class MyRobot(wpilib.TimedRobot):
+    def __init__(self):
+        super().__init__()
+        # Your image processing code will be launched via a stub that will set up logging and initialize NetworkTables
+        # to talk to your robot code.
+        # https://robotpy.readthedocs.io/en/stable/vision/roborio.html#important-notes
+
+        wpilib.CameraServer.launch("vision.py:main")