Fix 'Edit Settings' problem for Win64 (#312)

src/main.c

@@ -1209,7 +1209,7 @@ show_error(void)
 
 
 static void *
-align(void *ptr, DWORD alig)
+align(void *ptr, uintptr_t alig)
 {
 	uintptr_t ul = (uintptr_t)ptr;
 	ul += alig;
@@ -1778,7 +1778,7 @@ show_settings_dialog()
 #define WIDTH (460)
 #define LABEL_WIDTH (90)
 
-	unsigned char mem[8192], *p;
+	unsigned char mem[16*1024], *p;
 	const struct mg_option *options;
 	DWORD style;
 	DLGTEMPLATE *dia = (DLGTEMPLATE *)mem;