Broke out into two macro sections

docs/User-Manual.md

@@ -13,6 +13,8 @@
   - [Interpreter](#interpreter)
 - [Language Details](#language-details)
 - [Macro Systems](#macro-systems)
+  - [Syntax Rules](#syntax-rules)
+  - [Explicit Renaming](#explicit-renaming)
   - [Debugging](#debugging)
 - [Multithreaded Programming](#multithreaded-programming)
   - [Thread Safety](#thread-safety)
@@ -164,9 +166,7 @@ A [R<sup>7</sup>RS Compliance Chart](Scheme-Language-Compliance.md) lists differ
 
 # Macro Systems
 
-## Overview
-
-Cyclone provides two macro systems. 
+## Syntax Rules
 
 High-level hygienic macros may be created using `syntax-rules`. This system is based on a template language specified by R<sup>7</sup>RS. The specification goes into more detail on how to work with these macros:
 
@@ -176,7 +176,11 @@ High-level hygienic macros may be created using `syntax-rules`. This system is b
          (if test
              (begin result1 result2 ...)))))
 
-Alternatively a low-level explicit renaming (ER) macros system is also provided that allows defining macros using Scheme code, in a similar manner as `defmacro`. This macro system provides the convenience functions `(rename identifier)` to hygienically rename an identifier and `(compare identifier1 identifier2)` to compare two identifiers:
+## Explicit Renaming
+
+Alternatively a low-level explicit renaming (ER) macros system is also provided that allows defining macros using Scheme code, in a similar manner as `defmacro`. 
+
+This macro system provides the convenience functions `(rename identifier)` to hygienically rename an identifier and `(compare identifier1 identifier2)` to compare two identifiers:
 
     (define-syntax when
       (er-macro-transformer