[PATCH] Document git-fetch options

Add documentation for git-fetch options

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

Documentation/git-fetch.txt

@@ -26,6 +26,12 @@ OPTIONS
 -------
 include::pull-fetch-param.txt[]
 
+-u, \--update-head-ok::
+	By default 'git-fetch' refuses to update the head which
+	corresponds to the current branch.  This flag disables the
+	check.  Note that fetching into the current branch will not
+	update the index and working directory, so use it with care.
+
 
 Author
 ------

Documentation/pull-fetch-param.txt

@@ -80,3 +80,14 @@
           <ref>: when pulling/fetching, and <ref>:<ref> when
           pushing.  That is, do not store it locally if
           fetching, and update the same name if pushing.
+
+-a, \--append::
+	Append ref names and object names of fetched refs to the
+	existing contents of $GIT_DIR/FETCH_HEAD.  Without this
+	option old data in $GIT_DIR/FETCH_HEAD will be overwritten.
+
+-f, \--force::
+	Usually, the command refuses to update a local ref that is
+	not an ancestor of the remote ref used to overwrite it.
+	This flag disables the check.  What this means is that the
+	local repository can lose commits; use it with care.