MDL-22054 converting block name strings to pluginname

AMOS START
 MOV [recentactivity,core],[pluginname,block_recent_activity]
AMOS END

blocks/recent_activity/block_recent_activity.php

@@ -2,7 +2,7 @@
 
 class block_recent_activity extends block_base {
     function init() {
-        $this->title = get_string('recentactivity');
+        $this->title = get_string('plguinname', 'block_recentactivity');
         $this->version = 2007101509;
     }
 

blocks/recent_activity/lang/en/block_recent_activity.php

@@ -0,0 +1,26 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Strings for component 'block_recent_activity', language 'en', branch 'MOODLE_20_STABLE'
+ *
+ * @package   block_recent_activity
+ * @copyright 1999 onwards Martin Dougiamas  {@link http://moodle.com}
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+$string['pluginname'] = 'Recent Activity';