lower case version of todo kw triggers refile bug

[Samuel Wales <samologist@gmail.com>]

When I have a lower case version of a todo kw as the first
word in a header, refile skips the header.  Or so it seems.

I suspect that regexp matching for todo keywords in refile
code might be allowing lower case versions of those
keywords.  There was a fix for a similar problem a while
back and that fix seems to work.  So perhaps there is more than one
todo regexp?  That would be strange, but if so, then perhaps they can
be refactored.

To reproduce, try refile with ido and full paths.

Thanks.

-- 
Myalgic encephalomyelitis causes death and severe suffering.
You can get it any time and never recover.  Conflicts of
interest are destroying research.  Do science and justice
matter to you?  http://www.meactionuk.org.uk/What_Is_ME_What_Is_CFS.htm