Spelling error fixed.

TODO

@@ -11,7 +11,7 @@ Before the next release
 ** The text-mass file should contain some redundancy. At a minimum, it
    should store the text number and text length of each text, so that
    there is absolutely no risk that the wrong text is displayed. (That
-   has acutally happened more than once due to faulty hardware or
+   has actually happened more than once due to faulty hardware or
    operating systems--we should do better.)
 
 ** Documentation Issues