update: mention how update can be used to cancel an uncommitted merge stable

update: mention how update can be used to cancel an uncommitted merge

--- a/mercurial/commands.py	Tue Jul 10 11:15:22 2012 +0200
+++ b/mercurial/commands.py	Tue Jul 10 21:26:18 2012 +0200
@@ -5639,6 +5639,9 @@
     3. With the -C/--clean option, uncommitted changes are discarded and
        the working directory is updated to the requested changeset.
 
+    To cancel an uncommitted merge (and lose your changes), use
+    :hg:`update --clean .`.
+
     Use null as the changeset to remove the working directory (like
     :hg:`clone -U`).