Document the use of "current directory" as pull source.

The repository to pull from can be a local repository, and as a
special case the current directory can be specified to perform
merges across local branches.

Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-pull.txt

@@ -19,6 +19,9 @@ When only one ref is downloaded, runs 'git resolve' to merge it
 into the local HEAD.  Otherwise uses 'git octopus' to merge them
 into the local HEAD.
 
+Note that you can use '.' (current directory) as the
+<repository> to pull from the local repository -- this is useful
+when merging local branches into the current branch.
 
 OPTIONS
 -------

Documentation/tutorial.txt

@@ -1028,7 +1028,9 @@ multiple working trees, but disk space is cheap these days.
 
 [NOTE]
 You could even pull from your own repository by
-giving '.' as <remote-repository> parameter to `git pull`.
+giving '.' as <remote-repository> parameter to `git pull`.  This
+is useful when you want to merge a local branch (or more, if you
+are making an Octopus) into the current branch.
 
 It is likely that you will be pulling from the same remote
 repository from time to time. As a short hand, you can store