Merge branch 'develop' into feature/sax2

include/nlohmann/json_fwd.hpp

@@ -21,7 +21,7 @@ This serializer ignores the template arguments and uses ADL
 ([argument-dependent lookup](http://en.cppreference.com/w/cpp/language/adl))
 for serialization.
 */
-template<typename = void, typename = void>
+template<typename T = void, typename SFINAE = void>
 struct adl_serializer;
 
 template<template<typename U, typename V, typename... Args> class ObjectType =