String changes in Yelp

[Don Scorgie <Don Scorgie org>]

3 changes:

yelp-print.c: Title of the dialog now marked for translation

yelp-search.c: Error messages are less crypic and (slightly) more
informative.  They also no longer contain rubbish I put in while testing
and forgot about when merging :P

yelp-toc.c: Remove the quote marks around "TOC file" in an error
message.  These weren't really quote marks, they were garbage left by
emacs and they served no purpose.

Don