Fix various reference issues in documentation

Co-Authored-By: Riley Shaw <30989490+ShineyDev@users.noreply.github.com>

docs/ext/commands/api.rst

@@ -42,7 +42,7 @@ Event Reference
 These events function similar to :ref:`the regular events <discord-api-events>`, except they
 are custom to the command extension module.
 
-.. function:: on_command_error(ctx, error)
+.. function:: discord.ext.commands.on_command_error(ctx, error)
 
     An error handler that is called when an error is raised
     inside a command either through user input error, check
@@ -55,7 +55,7 @@ are custom to the command extension module.
     :param error: The error that was raised.
     :type error: :class:`.CommandError` derived
 
-.. function:: on_command(ctx)
+.. function:: discord.ext.commands.on_command(ctx)
 
     An event that is called when a command is found and is about to be invoked.
 
@@ -65,7 +65,7 @@ are custom to the command extension module.
     :param ctx: The invocation context.
     :type ctx: :class:`.Context`
 
-.. function:: on_command_completion(ctx)
+.. function:: discord.ext.commands.on_command_completion(ctx)
 
     An event that is called when a command has completed its invocation.
 
@@ -374,6 +374,9 @@ Exceptions
 .. autoexception:: discord.ext.commands.BadUnionArgument
     :members:
 
+.. autoexception:: discord.ext.commands.BadLiteralArgument
+    :members:
+
 .. autoexception:: discord.ext.commands.PrivateMessageOnly
     :members:
 
@@ -533,6 +536,7 @@ Exception Hierarchy
                         - :exc:`~.commands.TooManyFlags`
                         - :exc:`~.commands.MissingRequiredFlag`
                 - :exc:`~.commands.BadUnionArgument`
+                - :exc:`~.commands.BadLiteralArgument`
                 - :exc:`~.commands.ArgumentParsingError`
                     - :exc:`~.commands.UnexpectedQuoteError`
                     - :exc:`~.commands.InvalidEndOfQuotedStringError`

docs/ext/commands/commands.rst

@@ -761,7 +761,7 @@ When our commands fail to parse we will, by default, receive a noisy error in ``
 that an error has happened and has been silently ignored.
 
 In order to handle our errors, we must use something called an error handler. There is a global error handler, called
-:func:`on_command_error` which works like any other event in the :ref:`discord-api-events`. This global error handler is
+:func:`.on_command_error` which works like any other event in the :ref:`discord-api-events`. This global error handler is
 called for every error reached.
 
 Most of the time however, we want to handle an error local to the command itself. Luckily, commands come with local error