Minor bug fixes for documentation.

src/doc/02_building.md

@@ -43,6 +43,4 @@ The advantage is that if the container images have already been built, `docker-c
 
 ## Further reading
 
-[**Introduction**](index.html)
-
 [How to use the software](@ref using)

src/doc/03_using.md

@@ -1,6 +1,6 @@
 # How to use this software # {#using}
 
-Before the software is run, it will need to be built, which is described in [How to build this software](@ref building) and in `[Native Linux build](@ref native).
+Before the software is run, it will need to be built, which is described in [How to build this software](@ref building) and in [Native Linux build](@ref native).
 
 There are essentially two main ways to use this software.  The easy method is to run the software in containers using Docker.  The alternative method is to run the software in multiple separate windows on a computer equipped with the Linux operating system.  Each of these will be described below.  
 

src/doc/04_native.md

@@ -63,6 +63,6 @@ This is how to create the original `dlms-cim-1.0.0-Source.tar.gz` is created.
 
 This simply removes all of the built targets and intermediate files to prepare for a fresh build.
 
-[Introduction](index.html)
+## Further reading
 
-[How to use the software](@ref using)
+[How to modify the software](@ref design)

src/doc/05_design.md

@@ -1,4 +1,4 @@
-# Design {#design}
+# How to modify the software {#design}
 The software is composed of a number of pieces, which together make up the simulation.  The components are:
 
     - Meter simulator(s)