[Samba] msdfs documentation update

[Rob Naccarato]

I spent some time trying to figure out why my particular
dfs root wasn't working. I note in the documenation that
the symlink should be in all lowercase. It should be
amended that the entire path to the symlink should all be
in lowercase as well.

For example, I had a share defined as such:

[pub]
	path = /export/home/Shares/public_share
	msdfs root = yes

and I could not make my Win95 (with the dfs client installed)
follow this symlink:

	damage1 -> msdfs:damage\test-share

Running a debug level of 10 reveals:

[2003/08/20 11:40:33, 5] msdfs/msdfs.c:is_msdfs_link(176)
  is_msdfs_link: /export/home/shares/public_share/* does not exist.

Curious. So I changed the directory name from .../Shares/... to
.../shares/... (along with my service definition) and it worked!

I have tested this with both 2.2.8a (compiled from source) and 
3.0.0beta2-1 (Debian package) and both behave the same way.

Thanks.

(looking forward to 3.0)