tweak software headings

index.md

@@ -83,7 +83,8 @@ This simple model makes them easy to understand and rely on.
 
 [FAQ](#frequently-asked-questions)  
 [software](#software)  
-[related tools](#related-tools)  
+  [plain text accounting tools](#plain-text-accounting-tools)  
+  [add-ons](#add-ons)  
   [data import/conversion](#data-importconversion)  
   [editor support](#editor-support)  
   [time logging](#time-logging)  
@@ -223,6 +224,8 @@ Glad you asked! See below, and also [comparisons](#comparisons). hledger's FAQ d
 
 ### software
 
+#### plain text accounting tools
+
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@@ -309,7 +312,9 @@ sm-Ledger      | 2007  |              | [squeak smalltalk][smalltalk-gh]
 
 <div class="seven columns">
 
-### related tools
+#### add-ons
+
+This and the sections below collect add-ons and helper tools related to the above (ledger, hledger, and beancount mostly).
 
 - [hledger-diff](http://hackage.haskell.org/package/hledger-diff) report differing transactions between two journals
 - [hledger-interest](http://hackage.haskell.org/package/hledger-interest) generate *ledger interest transactions