Add default hash for std::pair and std::tuple... slight code reorganization.

parallel_hashmap/phmap.h

@@ -47,9 +47,9 @@
 #include <cassert>
 #include <atomic>
 
+#include "phmap_fwd_decl.h"
 #include "phmap_utils.h"
 #include "phmap_base.h"
-#include "phmap_fwd_decl.h"
 
 #if PHMAP_HAVE_STD_STRING_VIEW
     #include <string_view>
@@ -4047,6 +4047,7 @@ struct HashEq<std::wstring_view> : StringHashEqT<wchar_t> {};
 #endif
 
 // Supports heterogeneous lookup for pointers and smart pointers.
+// -------------------------------------------------------------
 template <class T>
 struct HashEq<T*> 
 {
@@ -4068,6 +4069,7 @@ struct HashEq<T*>
 
 private:
     static const T* ToPtr(const T* ptr) { return ptr; }
+
     template <class U, class D>
     static const T* ToPtr(const std::unique_ptr<U, D>& ptr) {
         return ptr.get();