Rename keyboard XML resource files

 * <Keyboard> XML file should be kbd_*.xml
 * <Row> XML file should be rows_*.xml or row_*.xml
 * <Key> XML file should be key_*.xml or keys_*.xml
 * <key-style> XML file should be key_styles_*.xml

Change-Id: Ie57d5d78389c13d6c066ace4e3588518d1f25f13