add patch file against ujson4c library

- fix a bug in UJObjectUnpack() function with assignment of output
  parameters ( esnme/ujson4c#10 )
- fix a bug in UUJDecod() function with un-checked mem allocation
  ( esnme/ujson4c#9 )

ujson4c.diff

@@ -0,0 +1,70 @@
+diff --git a/src/ujdecode.c b/src/ujdecode.c
+index 4b5a62d..161d909 100644
+--- a/src/ujdecode.c
++++ b/src/ujdecode.c
+@@ -686,10 +686,10 @@ int UJObjectUnpack(UJObject objObj, int keys, const char *format, const wchar_t
+ 	int ki;
+ 	int ks = 0;
+ 	const wchar_t *keyNames[64];
+-  va_list args;
+-  UJObject *outValue;
++	UJObject *outValues[64];
++	va_list args;
++	UJObject *outValue;
+
+-  va_start(args, _keyNames);
+
+   if (!UJIsObject(objObj))
+ 	{
+@@ -703,10 +703,14 @@ int UJObjectUnpack(UJObject objObj, int keys, const char *format, const wchar_t
+ 		return -1;
+ 	}
+
++	va_start(args, _keyNames);
+ 	for (ki = 0; ki < keys; ki ++)
+ 	{
+ 		keyNames[ki] = _keyNames[ki];
++		outValue = va_arg(args, UJObject *);
++		outValues[ki] = outValue;
+ 	}
++	va_end(args);
+
+ 	while (UJIterObject(&iter, &key, &value))
+ 	{
+@@ -731,12 +735,10 @@ int UJObjectUnpack(UJObject objObj, int keys, const char *format, const wchar_t
+
+ 			found ++;
+
+-      outValue = va_arg(args, UJObject);
+-
+-      if (outValue != NULL)
+-      {
+-  			*outValue = value;
+-      }
++			if (outValues[ki]) 
++			{
++				*outValues[ki] = value;
++			}
+ 			keyNames[ki] = NULL;
+
+ 			if (ki == ks)
+@@ -746,7 +748,6 @@ int UJObjectUnpack(UJObject objObj, int keys, const char *format, const wchar_t
+ 		}
+ 	}
+
+-  va_end(args);
+
+ 	return found;
+ }
+@@ -788,6 +789,11 @@ UJObject UJDecode(const char *input, size_t cbInput, UJHeapFuncs *hf, void **out
+ 		decoder.realloc = realloc;
+ 		cbInitialHeap = 16384;
+ 		initialHeap = malloc(cbInitialHeap);
++
++		if (initialHeap == NULL)
++		{
++			return NULL;
++		}
+ 	}
+ 	else
+ 	{