Make �iterator_category_value inline instead of static

Author: Morwenn

include/cpp-sort/adapters/hybrid_adapter.h

@@ -43,20 +43,17 @@ namespace cppsort
         // Associate a priority to iterator categories, there is
         // probably a trick to automate that...
 
-        namespace // GitHub issue #158
-        {
-            template<typename>
-            std::size_t iterator_category_value;
+        template<typename>
+        std::size_t iterator_category_value;
 
-            template<>
-            constexpr std::size_t iterator_category_value<std::random_access_iterator_tag> = 2;
+        template<>
+        inline constexpr std::size_t iterator_category_value<std::random_access_iterator_tag> = 2;
 
-            template<>
-            constexpr std::size_t iterator_category_value<std::bidirectional_iterator_tag> = 1;
+        template<>
+        inline constexpr std::size_t iterator_category_value<std::bidirectional_iterator_tag> = 1;
 
-            template<>
-            constexpr std::size_t iterator_category_value<std::forward_iterator_tag> = 0;
-        }
+        template<>
+        inline constexpr std::size_t iterator_category_value<std::forward_iterator_tag> = 0;
 
         // Avoid just a bit of redundancy
         template<typename Iterator, std::size_t N>