[PATCH 2 of 3 V2] help: adding example 'extras' printing to 'hg help templates'

[Matthew Turk]

# HG changeset patch
# User Matthew Turk <matthewturk at gmail.com>
# Date 1384556942 18000
#      Fri Nov 15 18:09:02 2013 -0500
# Node ID b69f7178f1da0a7dda97a6d5c8ccbf138579a73e
# Parent  0c27d52646b082ce934ab744ad5f3a28d4f9119a
help: adding example 'extras' printing to 'hg help templates'

diff -r 0c27d52646b0 -r b69f7178f1da mercurial/help/templates.txt
--- a/mercurial/help/templates.txt	Fri Nov 15 16:53:54 2013 -0500
+++ b/mercurial/help/templates.txt	Fri Nov 15 18:09:02 2013 -0500
@@ -102,3 +102,7 @@
 - Invert the firstline filter, i.e. everything but the first line::
 
    $ hg log -r 0 --template "{sub(r'^.*\n?\n?', '', desc)}\n"
+
+- Display the contents of the 'extra' field, one per line::
+
+  $ hg log -r 0 --template "{join(extras, '\n')}\n"