Document a couple of missing command-line options.

This patch adds documentation to quite a few command-line options.

Signed-off-by: Nikolai Weibull <nikolai@bitwi.se>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/Documentation/git-read-tree.txt b/Documentation/git-read-tree.txt
index e219c6a..7be0cbd 100644
--- a/Documentation/git-read-tree.txt
+++ b/Documentation/git-read-tree.txt
@@ -30,6 +30,10 @@
 -m::
 	Perform a merge, not just a read.
 
+--reset::
+
+        Same as -m except that unmerged entries will be silently ignored.
+
 -u::
 	After a successful merge, update the files in the work
 	tree with the result of the merge.