MDL-29029 move dbtransfer to admin tools

AMOS BEGIN
 CPY [dbexport,core_dbtransfer],[pluginname,tool_dbtransfer]
 MOV [dbexport,core_dbtransfer],[dbexport,tool_dbtransfer]
 MOV [dbtransfer,core_dbtransfer],[dbtransfer,tool_dbtransfer]
 MOV [exportdata,core_dbtransfer],[exportdata,tool_dbtransfer]
 MOV [notargetconectexception,core_dbtransfer],[notargetconectexception,tool_dbtransfer]
 MOV [pluginname,core_dbtransfer],[pluginname,tool_dbtransfer]
 MOV [transferdata,core_dbtransfer],[transferdata,tool_dbtransfer]
 MOV [transferdbintro,core_dbtransfer],[transferdbintro,tool_dbtransfer]
 MOV [transferdbtoserver,core_dbtransfer],[transferdbtoserver,tool_dbtransfer]
 MOV [transferringdbto,core_dbtransfer],[transferringdbto,tool_dbtransfer]
AMOS END

lib/pluginlib.php

@@ -367,7 +367,7 @@ class plugin_manager {
             ),
 
             'tool' => array(
-                'bloglevelupgrade', 'capability', 'generator', 'health',
+                'bloglevelupgrade', 'capability', 'dbtransfer', 'generator', 'health',
                 'innodb', 'langimport', 'profiling', 'unittest', 'unsuproles'
             ),