Add BOOST_NVP convenience macro

doc/nvp.qbk

@@ -54,6 +54,8 @@ template<class T>
 const nvp<T> make_nvp(const char* name, T& value) noexcept;
 
 } /* boost */
+
+#define BOOST_NVP(object) ``['see below]``
 ```
 
 [section Constructors]
@@ -86,6 +88,14 @@ noexcept;`]
 
 [endsect]
 
+[section Macros]
+
+[variablelist
+[[`#define BOOST_NVP(object) see below`]
+[Expands to `boost::make_nvp(BOOST_STRINGIZE(object), object)`.]]]
+
+[endsect]
+
 [endsect]
 
 [section Acknowledgments]