Bug#460397: add "use MIME::...;" to man pages

[jidanni at jidanni.org]

Package: libmime-perl
Version: 5.425-1
Severity: minor
X-Debbugs-Cc: eryq at zeegee.com

All the man pages that say

       Before reading further, you should see MIME::Tools to make sure that
       you understand where this module fits into the grand scheme of things.
       Go on, do it now.  I'll wait.

forget to add their e.g.,

	use MIME::Head;

Sure, there are some use MIME::whatevers on man MIME::Tools, but not
all of them.

P.S., error messages like
     "can't build entity: no body, and not multipart"
should say what line number they occurred on.
(caused with MIME::Head->attach()).