Fix update_po_templates.php to support the plural and context variants of _m() in plugins

plugins/Sample/hello.php

@@ -119,13 +119,15 @@ class HelloAction extends Action
     }
 
     /**
-     * show content in the content area
+     * Show content in the content area
      *
      * The default StatusNet page has a lot of decorations: menus,
      * logos, tabs, all that jazz. This method is used to show
      * content in the content area of the page; it's the main
      * thing you want to overload.
      *
+     * This method also demonstrates use of a plural localized string.
+     *
      * @return void
      */
 
@@ -138,7 +140,9 @@ class HelloAction extends Action
             $this->element('p', array('class' => 'greeting'),
                            sprintf(_m('Hello, %s'), $this->user->nickname));
             $this->element('p', array('class' => 'greeting_count'),
-                           sprintf(_m('I have greeted you %d time(s).'),
+                           sprintf(_m('I have greeted you %d time.',
+                                      'I have greeted you %d times.',
+                                      $this->gc->greeting_count),
                                    $this->gc->greeting_count));
         }
     }

plugins/Sample/locale/Sample.po

@@ -0,0 +1,56 @@
+# SOME DESCRIPTIVE TITLE.
+# Copyright (C) YEAR THE PACKAGE'S COPYRIGHT HOLDER
+# This file is distributed under the same license as the PACKAGE package.
+# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+#
+#, fuzzy
+msgid ""
+msgstr ""
+"Project-Id-Version: PACKAGE VERSION\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2010-02-24 16:33-0800\n"
+"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+"Language-Team: LANGUAGE <LL@li.org>\n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=CHARSET\n"
+"Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=INTEGER; plural=EXPRESSION;\n"
+
+#: hello.php:115 SamplePlugin.php:266
+msgid "Hello"
+msgstr ""
+
+#: hello.php:117 hello.php:141
+#, php-format
+msgid "Hello, %s"
+msgstr ""
+
+#: hello.php:138
+msgid "Hello, stranger!"
+msgstr ""
+
+#: hello.php:143
+#, php-format
+msgid "I have greeted you %d time."
+msgid_plural "I have greeted you %d times."
+msgstr[0] ""
+msgstr[1] ""
+
+#: SamplePlugin.php:266
+msgid "A warm greeting"
+msgstr ""
+
+#: SamplePlugin.php:277
+msgid "A sample plugin to show basics of development for new hackers."
+msgstr ""
+
+#: User_greeting_count.php:163
+#, php-format
+msgid "Could not save new greeting count for %d"
+msgstr ""
+
+#: User_greeting_count.php:176
+#, php-format
+msgid "Could not increment greeting count for %d"
+msgstr ""