64bit hash performance boost

We want to include the second part of the 64bit value - we also introduce a small prime to improve distribution.

Result is SymmetricDifference and Difference being 10-20x faster for large 64bit data

Source/simba.container_dict.pas

@@ -172,7 +172,7 @@ class function TDictionary<K,V>.HashInt32(constref k: Int32): UInt32;
 
 class function TDictionary<K,V>.HashInt64(constref k: Int64): UInt32;
 begin
-  Result := UInt32(k);
+  Result := (UInt32(k) * 31) xor UInt32(k shr 32);
 end;
 
 // FNV