Lower some build depends to build on squeeze.

+ gcc from 4.7 to 4.4.
+ libfuse-dev from 2.8.4-1.4 to 2.8.4-1.1.
Fix second part of issue #1441.
When running 'grub_probe --target=device ...' and it returns multiple
results (as if device is a mirror), only take the first line/entry.
Remove extra slash before the @ in two xasprintf() calls.
Fix for grub-2.0 build on systems with eglibc-2.16
+ http://lists.gnu.org/archive/html/grub-devel/2012-07/msg00007.html
@subsection after @itemize fix in grub-dev.texi.
Update changelog for 2.00-13ubuntu3+zfs3~raring release