Update readme with latest TFBMTool-alt changes

TFBMTool-alt/TFBMTool_main.c

@@ -7,7 +7,7 @@ int wmain(int ac, wchar_t **av)
     wprintf(L"Usage: %S (/x|/p) in.[bmp|png] [palette.bmp]\n"
 	    "palette.bmp is used if (and only if) the input file is a 8-bit file with a palette.\n"
 	    "For /x, palette.bmp is required for 8-bit files, and is used as the palette for the input file.\n"
-	    "For /p, palette.bmp is optional, and if specified, will contain the file's palette.\n"
+	    "For /p, palette.bmp is optional, and if specified, will contain the file's palette\n"
 		"in the TFPA format.", av[0]);
     return 0;
   }

readme.md

@@ -95,7 +95,8 @@ This one always overwrites the TFBM file in place, because I've never seen anyon
 Usage (extraction): `./TFBMTool-alt /x tfbm_file.[bmp|png] [palette_XXX.bmp]`  
 The palette is optional (and not used) for 24-bpp and 32-bpp TFBM files. It is mandatory for 8-bpp TFBM files, and the extracted file will be a 8-bpp PNG file with a palette.  
 
-Usage (repacking): `./TFBMTool-alt /p tfbm_file.[bmp|png]`
+Usage (repacking): `./TFBMTool-alt /p tfbm_file.[bmp|png] [palette_XXX.bmp]`  
+The palette is not used for 24-bpp and 32-bpp PNG files. For 8-bpp PNG files, it is optional, and if specified, the PNG file's palette is dumped into it.
 
 ### extractBM-alt
 A C rewrite of Riatre's extractBM using TFBMTool-alt. It searches for every png and bmp files in the current directory and its subdirectories (recursively), and calls TFBMTool-alt on them.