More privatization, and some error helpers (#2976)

* More privatization, and some error helpers

This makes a lot more things private. Continued from #2967, fixes #2984
Adds public methods for various things.

Below is a brief summary of things available elsewhere, though this
particular set of changes may warrant a detailed section in the release notes.

 - bot.db.locale -> redbot.core.i18n.get_locale
   - Note: This one already existed.
 - bot.db.help -> redbot.core.commands.help.HelpSettings
 - bot db whitelist/blaclist? -> bot.allowed_by_whitelist_blacklist
   - This has also been made a single cannonical function for this
   purpose including check usage
 - bot color? -> bot.get_embed_color/bot.get_embed_colour
 - bot.id.api_tokens? ->

   - bot.get_shared_api_tokens
   - bot.set_shared_api_tokens
   - bot.remove_shared_api_tokens

 -bot.db.prefix -> bot.get_valid_prefixes
   - (Note: This is a wrapper around bot.get_prefix)

 Other changes include
  - removing `bot.counter` as it was never used anywhere
  - Adding properties with helpful error messages for moved and renamed
  things
  - making bot.uptime a property with an error on set
  - adding a migration to the bot config for shared_api_tokens

* Remove overly encompassing message redaction, eval is a risk, dont run in dev if you cant manage it

* address Flame's feedback

* rephrase example

* changelog extras

* You saw nothing

redbot/core/commands/help.py

@@ -1,3 +1,8 @@
+# Warning: The implementation below touches several private attributes.
+# While this implementation will be updated, and public interfaces maintained, derived classes
+# should not assume these private attributes are version safe, and use the provided HelpSettings
+# class for these settings.
+
 # This is a full replacement of discord.py's help command
 #
 # At a later date, there should be things added to support extra formatter
@@ -29,6 +34,7 @@
 
 import asyncio
 from collections import namedtuple
+from dataclasses import dataclass
 from typing import Union, List, AsyncIterator, Iterable, cast
 
 import discord
@@ -40,7 +46,7 @@ from ..i18n import Translator
 from ..utils import menus, fuzzy_command_search, format_fuzzy_results
 from ..utils.chat_formatting import box, pagify
 
-__all__ = ["red_help", "RedHelpFormatter"]
+__all__ = ["red_help", "RedHelpFormatter", "HelpSettings"]
 
 T_ = Translator("Help", __file__)
 
@@ -53,6 +59,36 @@ EmbedField = namedtuple("EmbedField", "name value inline")
 EMPTY_STRING = "\N{ZERO WIDTH SPACE}"
 
 
+@dataclass(frozen=True)
+class HelpSettings:
+    """
+    A representation of help settings.
+    """
+
+    page_char_limit: int = 1000
+    max_pages_in_guild: int = 2
+    use_menus: bool = False
+    show_hidden: bool = False
+    verify_checks: bool = True
+    verify_exists: bool = False
+    tagline: str = ""
+
+    # Contrib Note: This is intentional to not accept the bot object
+    # There are plans to allow guild and user specific help settings
+    # Adding a non-context based method now would involve a breaking change later.
+    # At a later date, more methods should be exposed for non-context based creation.
+    #
+    # This is also why we aren't just caching the
+    # current state of these settings on the bot object.
+    @classmethod
+    async def from_context(cls, context: Context):
+        """
+        Get the HelpSettings for the current context
+        """
+        settings = await context.bot._config.help.all()
+        return cls(**settings)
+
+
 class NoCommand(Exception):
     pass