message: Renames AXOM_DEBUG_VAR macro to AXOM_UNUSED_VAR
  There are several places in the code that we'd like to elide warnings
  about unused variables, e.g. for variables that are only used conditionally
  within compiler defines. A subset of these cases are for assert variables.
diff: /*!
  *
  - * \def AXOM_DEBUG_VAR(x)
  + * \def AXOM_UNUSED_VAR(x)
  * \brief Macro used to silence compiler warnings about variables
  * that are defined but not used.
  * \note The intent is to use this macro for variables that are only used
  - * for debugging purposes (e.g. in debug assertions). For example:
  + * within compiler defines, e.g. in debug assertions). For example:
  * \code
  *
  * double myVar = ...
  - * AXOM_DEBUG_VAR(myVar);
  + * AXOM_UNUSED_VAR(myVar);
  *
  * // code emits the following warning in release builds
  * // if extra warnings are enabled and this macro is not called
  *
  * \endcode
  */
  -#define AXOM_DEBUG_VAR(_x) static_cast<void>(_x)
  +#define AXOM_UNUSED_VAR(_x) static_cast<void>(_x)
  /*!
  * \def AXOM_DEBUG_PARAM(x)
  