[PATCH 5 of 7 STABLE] doc: add description about re-opening closed heads to 'Head, closed branch' in glossary

[FUJIWARA Katsunori]

# HG changeset patch
# User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
# Date 1335108789 -32400
# Branch stable
# Node ID 900af050dd4ed67f68d9e2ba7fcd90e510d7c647
# Parent  189c7f6d9a2a9c62d51fc654a6255c3f556da6b3
doc: add description about re-opening closed heads to 'Head, closed branch' in glossary

diff -r 189c7f6d9a2a -r 900af050dd4e mercurial/help/glossary.txt
--- a/mercurial/help/glossary.txt	Mon Apr 23 00:33:09 2012 +0900
+++ b/mercurial/help/glossary.txt	Mon Apr 23 00:33:09 2012 +0900
@@ -237,6 +237,9 @@
     closed when all its heads are closed and consequently is not
     listed by :hg:`branches`.
 
+    Closed heads can be re-opened by committing new changeset as the
+    child of the changeset that marks a head as closed.
+
 Head, repository
     A topological head which has not been closed.