[AC 21.5] Spelling corrections

PATCH 21.5 Recently, a number of patches have been sent to the Linux Kernel Mailing List that korrect mispelt wurds.  The patches were created by the author of codespell: http://git.profusion.mobi/cgit.cgi/lucas/codespell/ I tried running codespell over the XEmacs repository to see what it turned up.  Here is the result.  I corrected some grammar while I was at it.  Some of these "corrections" may be due to me having an American English dictionary, instead of a British English dictionary. Feel free to point out corrections that shouldn't be made. (This doesn't mean that no misspellings remain, just that we fixed some common ones.) I'm attaching the patch, because I don't trust gmail to not mangle the whitespace if I copy and paste it.