📝 docs(readme): update TOC (#44)

README.md

@@ -45,11 +45,11 @@ pip install dataclassish
 ## Documentation
 
 - [Getting Started](#getting-started)
-  - [Working with a `@dataclass`](#working-with-a-dataclass)
-  - [Working with a `dict`](#working-with-a-dict)
-  - [The `__replace__` Method](#the-__replace__-method)
-  - [Registering in a Custom Type](#registering-in-a-custom-type)
-- [Adding a Second Argument](#adding-a-second-argument)
+- [Replacing a `@dataclass`](#replacing-a-dataclass)
+- [Replacing a `dict`](#replacing-a-dict)
+- [Replacing via the `__replace__` Method](#replacing-via-the-__replace__-method)
+- [Replacing a Custom Type](#replacing-a-custom-type)
+- [Nested Replacement](#nested-replacement)
 - [dataclass tools](#dataclass-tools)
 - [More tools](#more-tools)
 - [Converters](#converters)