expose base class ctors

include/jwt-cpp/traits/danielaparker-jsoncons/traits.h

@@ -63,6 +63,7 @@ namespace jwt {
 			};
 			class array_type : public json::array {
 			public:
+				using json::array::array;
 				value_type const& front() const { return this->operator[](0U); }
 			};
 			using string_type = std::string; // current limitation of traits implementation