Begin work on a data request API (#4045)

[Core] Data Deletion And Disclosure APIs

 - Adds a Data Deletion API
   - Deletion comes in a few forms based on who is requesting
   - Deletion must be handled by 3rd party
 - Adds a Data Collection Disclosure Command
   - Provides a dynamically generated statement from 3rd party
   extensions
 - Modifies the always available commands to be cog compatible
   - Also prevents them from being unloaded accidentally

redbot/cogs/streams/streams.py

@@ -79,6 +79,10 @@ class Streams(commands.Cog):
         self._ready_event: asyncio.Event = asyncio.Event()
         self._init_task: asyncio.Task = self.bot.loop.create_task(self.initialize())
 
+    async def red_delete_data_for_user(self, **kwargs):
+        """ Nothing to delete """
+        return
+
     def check_name_or_id(self, data: str) -> bool:
         matched = self.yt_cid_pattern.fullmatch(data)
         if matched is None: