anchor.diff:  $ sudo apt-get install cppcheck
   ----
   
  -[[concepts]]
  -Concepts
  -~~~~~~~~
  -
  -[[adding-custom-package-modules]]
  -Adding Custom Package Modules
  -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  +# Concepts
  +
  +## Adding Custom Package Modules
   
   Custom modules can be used to find programs, libraries and header files
   to include in your program.
   
  -[[adding-a-custom-module]]
  -Adding a custom module
  -++++++++++++++++++++++
  +### Adding a custom module
   
   The `cmake/modules/FindCppCheck.cmake` file contains the code to initialise a
   custom package module.
  
positive.code: find_package(CppCheck)
  ----
  
  [[parent-scope-variables]]
  Parent Scope Variables
  ^^^^^^^^^^^^^^^^^^^^^^
  
  The scope of variables when they are declared / changed is typically in
  the function of file the are called. To make a change to a variable
  
negative.code: set(ALL_ANALYSIS_TARGETS "${ALL_ANALYSIS_TARGETS}" PARENT_SCOPE)
  ----
  
  ## add_analysis macro
  
  The +add_analysis()+ macro in `cmake/analysis.cmake` is the core idea for this
  example. If cppcheck is available then a list of arguments are compiled
  