Reorganize [p]set command group (#5432)

* Reorganised Set command group

* Moved custominfo

* Tox styling

* Make `set locale&regionalformat` groups work same as server subcommands

* Use consistent method names for commands in `[p]set` group

* Update command names in docstrings

* Remove some weird rst formatting that bugs out my syntax highlighting

* Add checks to some command groups

* Update docs

* oops

* Minor fixes

* Move `[p]set api` group and its subcommands to other command groups

* Move `[p]set ownernotifications` group to other command groups

* black reformat

Co-authored-by: jack1142 <6032823+jack1142@users.noreply.github.com>

docs/getting_started.rst

@@ -225,7 +225,7 @@ Administrator
 ~~~~~~~~~~~~~
 
 The administrator is defined by its roles. You can set multiple admin roles
-with the ``[p]set addadminrole`` and ``[p]set removeadminrole`` commands.
+with the ``[p]set roles addadminrole`` and ``[p]set roles removeadminrole`` commands.
 
 For example, in the mod cog, an admin can use the ``[p]modset`` command
 which defines the cog settings.
@@ -235,7 +235,7 @@ Moderator
 ~~~~~~~~~
 
 A moderator is a step above the average users. You can set multiple moderator
-roles with the ``[p]set addmodrole`` and ``[p]set removemodrole`` commands.
+roles with the ``[p]set roles addmodrole`` and ``[p]set roles removemodrole`` commands.
 
 For example, in the filter cog, a mod will be able to use the various commands 
 under ``[p]filter`` (such as adding and removing filtered words), but they will